Fossil SCM

fossil-scm / extsrc / sqlite3.h
Blame History Raw 14336 lines
1
/*
2
** 2001-09-15
3
**
4
** The author disclaims copyright to this source code. In place of
5
** a legal notice, here is a blessing:
6
**
7
** May you do good and not evil.
8
** May you find forgiveness for yourself and forgive others.
9
** May you share freely, never taking more than you give.
10
**
11
*************************************************************************
12
** This header file defines the interface that the SQLite library
13
** presents to client programs. If a C-function, structure, datatype,
14
** or constant definition does not appear in this file, then it is
15
** not a published API of SQLite, is subject to change without
16
** notice, and should not be referenced by programs that use SQLite.
17
**
18
** Some of the definitions that are in this file are marked as
19
** "experimental". Experimental interfaces are normally new
20
** features recently added to SQLite. We do not anticipate changes
21
** to experimental interfaces but reserve the right to make minor changes
22
** if experience from use "in the wild" suggest such changes are prudent.
23
**
24
** The official C-language API documentation for SQLite is derived
25
** from comments in this file. This file is the authoritative source
26
** on how SQLite interfaces are supposed to operate.
27
**
28
** The name of this file under configuration management is "sqlite.h.in".
29
** The makefile makes some minor changes to this file (such as inserting
30
** the version number) and changes its name to "sqlite3.h" as
31
** part of the build process.
32
*/
33
#ifndef SQLITE3_H
34
#define SQLITE3_H
35
#include <stdarg.h> /* Needed for the definition of va_list */
36
37
/*
38
** Make sure we can call this stuff from C++.
39
*/
40
#ifdef __cplusplus
41
extern "C" {
42
#endif
43
44
45
/*
46
** Facilitate override of interface linkage and calling conventions.
47
** Be aware that these macros may not be used within this particular
48
** translation of the amalgamation and its associated header file.
49
**
50
** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
51
** compiler that the target identifier should have external linkage.
52
**
53
** The SQLITE_CDECL macro is used to set the calling convention for
54
** public functions that accept a variable number of arguments.
55
**
56
** The SQLITE_APICALL macro is used to set the calling convention for
57
** public functions that accept a fixed number of arguments.
58
**
59
** The SQLITE_STDCALL macro is no longer used and is now deprecated.
60
**
61
** The SQLITE_CALLBACK macro is used to set the calling convention for
62
** function pointers.
63
**
64
** The SQLITE_SYSAPI macro is used to set the calling convention for
65
** functions provided by the operating system.
66
**
67
** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
68
** SQLITE_SYSAPI macros are used only when building for environments
69
** that require non-default calling conventions.
70
*/
71
#ifndef SQLITE_EXTERN
72
# define SQLITE_EXTERN extern
73
#endif
74
#ifndef SQLITE_API
75
# define SQLITE_API
76
#endif
77
#ifndef SQLITE_CDECL
78
# define SQLITE_CDECL
79
#endif
80
#ifndef SQLITE_APICALL
81
# define SQLITE_APICALL
82
#endif
83
#ifndef SQLITE_STDCALL
84
# define SQLITE_STDCALL SQLITE_APICALL
85
#endif
86
#ifndef SQLITE_CALLBACK
87
# define SQLITE_CALLBACK
88
#endif
89
#ifndef SQLITE_SYSAPI
90
# define SQLITE_SYSAPI
91
#endif
92
93
/*
94
** These no-op macros are used in front of interfaces to mark those
95
** interfaces as either deprecated or experimental. New applications
96
** should not use deprecated interfaces - they are supported for backwards
97
** compatibility only. Application writers should be aware that
98
** experimental interfaces are subject to change in point releases.
99
**
100
** These macros used to resolve to various kinds of compiler magic that
101
** would generate warning messages when they were used. But that
102
** compiler magic ended up generating such a flurry of bug reports
103
** that we have taken it all out and gone back to using simple
104
** noop macros.
105
*/
106
#define SQLITE_DEPRECATED
107
#define SQLITE_EXPERIMENTAL
108
109
/*
110
** Ensure these symbols were not defined by some previous header file.
111
*/
112
#ifdef SQLITE_VERSION
113
# undef SQLITE_VERSION
114
#endif
115
#ifdef SQLITE_VERSION_NUMBER
116
# undef SQLITE_VERSION_NUMBER
117
#endif
118
119
/*
120
** CAPI3REF: Compile-Time Library Version Numbers
121
**
122
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
123
** evaluates to a string literal that is the SQLite version in the
124
** format "X.Y.Z" where X is the major version number (always 3 for
125
** SQLite3) and Y is the minor version number and Z is the release number.)^
126
** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
127
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
128
** numbers used in [SQLITE_VERSION].)^
129
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
130
** be larger than the release from which it is derived. Either Y will
131
** be held constant and Z will be incremented or else Y will be incremented
132
** and Z will be reset to zero.
133
**
134
** Since [version 3.6.18] ([dateof:3.6.18]),
135
** SQLite source code has been stored in the
136
** <a href="http://fossil-scm.org/">Fossil configuration management
137
** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
138
** a string which identifies a particular check-in of SQLite
139
** within its configuration management system. ^The SQLITE_SOURCE_ID
140
** string contains the date and time of the check-in (UTC) and a SHA1
141
** or SHA3-256 hash of the entire source tree. If the source code has
142
** been edited in any way since it was last checked in, then the last
143
** four hexadecimal digits of the hash may be modified.
144
**
145
** See also: [sqlite3_libversion()],
146
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
147
** [sqlite_version()] and [sqlite_source_id()].
148
*/
149
#define SQLITE_VERSION "3.53.0"
150
#define SQLITE_VERSION_NUMBER 3053000
151
#define SQLITE_SOURCE_ID "2026-04-07 09:15:21 c8121593fa455cd43b3878f8b65ebac47c07dab4b8ce081aa34b14fc9440afbc"
152
#define SQLITE_SCM_BRANCH "trunk"
153
#define SQLITE_SCM_TAGS ""
154
#define SQLITE_SCM_DATETIME "2026-04-07T09:15:21.538Z"
155
156
/*
157
** CAPI3REF: Run-Time Library Version Numbers
158
** KEYWORDS: sqlite3_version sqlite3_sourceid
159
**
160
** These interfaces provide the same information as the [SQLITE_VERSION],
161
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
162
** but are associated with the library instead of the header file. ^(Cautious
163
** programmers might include assert() statements in their application to
164
** verify that values returned by these interfaces match the macros in
165
** the header, and thus ensure that the application is
166
** compiled with matching library and header files.
167
**
168
** <blockquote><pre>
169
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
170
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
171
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
172
** </pre></blockquote>)^
173
**
174
** ^The sqlite3_version[] string constant contains the text of the
175
** [SQLITE_VERSION] macro. ^The sqlite3_libversion() function returns a
176
** pointer to the sqlite3_version[] string constant. The sqlite3_libversion()
177
** function is provided for use in DLLs since DLL users usually do not have
178
** direct access to string constants within the DLL. ^The
179
** sqlite3_libversion_number() function returns an integer equal to
180
** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns
181
** a pointer to a string constant whose value is the same as the
182
** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built
183
** using an edited copy of [the amalgamation], then the last four characters
184
** of the hash might be different from [SQLITE_SOURCE_ID].)^
185
**
186
** See also: [sqlite_version()] and [sqlite_source_id()].
187
*/
188
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
189
SQLITE_API const char *sqlite3_libversion(void);
190
SQLITE_API const char *sqlite3_sourceid(void);
191
SQLITE_API int sqlite3_libversion_number(void);
192
193
/*
194
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
195
**
196
** ^The sqlite3_compileoption_used() function returns 0 or 1
197
** indicating whether the specified option was defined at
198
** compile time. ^The SQLITE_ prefix may be omitted from the
199
** option name passed to sqlite3_compileoption_used().
200
**
201
** ^The sqlite3_compileoption_get() function allows iterating
202
** over the list of options that were defined at compile time by
203
** returning the N-th compile time option string. ^If N is out of range,
204
** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
205
** prefix is omitted from any strings returned by
206
** sqlite3_compileoption_get().
207
**
208
** ^Support for the diagnostic functions sqlite3_compileoption_used()
209
** and sqlite3_compileoption_get() may be omitted by specifying the
210
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
211
**
212
** See also: SQL functions [sqlite_compileoption_used()] and
213
** [sqlite_compileoption_get()] and the [compile_options pragma].
214
*/
215
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
216
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
217
SQLITE_API const char *sqlite3_compileoption_get(int N);
218
#else
219
# define sqlite3_compileoption_used(X) 0
220
# define sqlite3_compileoption_get(X) ((void*)0)
221
#endif
222
223
/*
224
** CAPI3REF: Test To See If The Library Is Threadsafe
225
**
226
** ^The sqlite3_threadsafe() function returns zero if and only if
227
** SQLite was compiled with mutexing code omitted due to the
228
** [SQLITE_THREADSAFE] compile-time option being set to 0.
229
**
230
** SQLite can be compiled with or without mutexes. When
231
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
232
** are enabled and SQLite is threadsafe. When the
233
** [SQLITE_THREADSAFE] macro is 0,
234
** the mutexes are omitted. Without the mutexes, it is not safe
235
** to use SQLite concurrently from more than one thread.
236
**
237
** Enabling mutexes incurs a measurable performance penalty.
238
** So if speed is of utmost importance, it makes sense to disable
239
** the mutexes. But for maximum safety, mutexes should be enabled.
240
** ^The default behavior is for mutexes to be enabled.
241
**
242
** This interface can be used by an application to make sure that the
243
** version of SQLite that it is linking against was compiled with
244
** the desired setting of the [SQLITE_THREADSAFE] macro.
245
**
246
** This interface only reports on the compile-time mutex setting
247
** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
248
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
249
** can be fully or partially disabled using a call to [sqlite3_config()]
250
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
251
** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the
252
** sqlite3_threadsafe() function shows only the compile-time setting of
253
** thread safety, not any run-time changes to that setting made by
254
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
255
** is unchanged by calls to sqlite3_config().)^
256
**
257
** See the [threading mode] documentation for additional information.
258
*/
259
SQLITE_API int sqlite3_threadsafe(void);
260
261
/*
262
** CAPI3REF: Database Connection Handle
263
** KEYWORDS: {database connection} {database connections}
264
**
265
** Each open SQLite database is represented by a pointer to an instance of
266
** the opaque structure named "sqlite3". It is useful to think of an sqlite3
267
** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
268
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
269
** and [sqlite3_close_v2()] are its destructors. There are many other
270
** interfaces (such as
271
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
272
** [sqlite3_busy_timeout()] to name but three) that are methods on an
273
** sqlite3 object.
274
*/
275
typedef struct sqlite3 sqlite3;
276
277
/*
278
** CAPI3REF: 64-Bit Integer Types
279
** KEYWORDS: sqlite_int64 sqlite_uint64
280
**
281
** Because there is no cross-platform way to specify 64-bit integer types
282
** SQLite includes typedefs for 64-bit signed and unsigned integers.
283
**
284
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
285
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
286
** compatibility only.
287
**
288
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
289
** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
290
** sqlite3_uint64 and sqlite_uint64 types can store integer values
291
** between 0 and +18446744073709551615 inclusive.
292
*/
293
#ifdef SQLITE_INT64_TYPE
294
typedef SQLITE_INT64_TYPE sqlite_int64;
295
# ifdef SQLITE_UINT64_TYPE
296
typedef SQLITE_UINT64_TYPE sqlite_uint64;
297
# else
298
typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
299
# endif
300
#elif defined(_MSC_VER) || defined(__BORLANDC__)
301
typedef __int64 sqlite_int64;
302
typedef unsigned __int64 sqlite_uint64;
303
#else
304
typedef long long int sqlite_int64;
305
typedef unsigned long long int sqlite_uint64;
306
#endif
307
typedef sqlite_int64 sqlite3_int64;
308
typedef sqlite_uint64 sqlite3_uint64;
309
310
/*
311
** If compiling for a processor that lacks floating point support,
312
** substitute integer for floating-point.
313
*/
314
#ifdef SQLITE_OMIT_FLOATING_POINT
315
# define double sqlite3_int64
316
#endif
317
318
/*
319
** CAPI3REF: Closing A Database Connection
320
** DESTRUCTOR: sqlite3
321
**
322
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
323
** for the [sqlite3] object.
324
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
325
** the [sqlite3] object is successfully destroyed and all associated
326
** resources are deallocated.
327
**
328
** Ideally, applications should [sqlite3_finalize | finalize] all
329
** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
330
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
331
** with the [sqlite3] object prior to attempting to close the object.
332
** ^If the database connection is associated with unfinalized prepared
333
** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
334
** sqlite3_close() will leave the database connection open and return
335
** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
336
** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
337
** it returns [SQLITE_OK] regardless, but instead of deallocating the database
338
** connection immediately, it marks the database connection as an unusable
339
** "zombie" and makes arrangements to automatically deallocate the database
340
** connection after all prepared statements are finalized, all BLOB handles
341
** are closed, and all backups have finished. The sqlite3_close_v2() interface
342
** is intended for use with host languages that are garbage collected, and
343
** where the order in which destructors are called is arbitrary.
344
**
345
** ^If an [sqlite3] object is destroyed while a transaction is open,
346
** the transaction is automatically rolled back.
347
**
348
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
349
** must be either a NULL
350
** pointer or an [sqlite3] object pointer obtained
351
** from [sqlite3_open()], [sqlite3_open16()], or
352
** [sqlite3_open_v2()], and not previously closed.
353
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
354
** argument is a harmless no-op.
355
*/
356
SQLITE_API int sqlite3_close(sqlite3*);
357
SQLITE_API int sqlite3_close_v2(sqlite3*);
358
359
/*
360
** The type for a callback function.
361
** This is legacy and deprecated. It is included for historical
362
** compatibility and is not documented.
363
*/
364
typedef int (*sqlite3_callback)(void*,int,char**, char**);
365
366
/*
367
** CAPI3REF: One-Step Query Execution Interface
368
** METHOD: sqlite3
369
**
370
** The sqlite3_exec() interface is a convenience wrapper around
371
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
372
** that allows an application to run multiple statements of SQL
373
** without having to use a lot of C code.
374
**
375
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
376
** semicolon-separated SQL statements passed into its 2nd argument,
377
** in the context of the [database connection] passed in as its 1st
378
** argument. ^If the callback function of the 3rd argument to
379
** sqlite3_exec() is not NULL, then it is invoked for each result row
380
** coming out of the evaluated SQL statements. ^The 4th argument to
381
** sqlite3_exec() is relayed through to the 1st argument of each
382
** callback invocation. ^If the callback pointer to sqlite3_exec()
383
** is NULL, then no callback is ever invoked and result rows are
384
** ignored.
385
**
386
** ^If an error occurs while evaluating the SQL statements passed into
387
** sqlite3_exec(), then execution of the current statement stops and
388
** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
389
** is not NULL then any error message is written into memory obtained
390
** from [sqlite3_malloc()] and passed back through the 5th parameter.
391
** To avoid memory leaks, the application should invoke [sqlite3_free()]
392
** on error message strings returned through the 5th parameter of
393
** sqlite3_exec() after the error message string is no longer needed.
394
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
395
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
396
** NULL before returning.
397
**
398
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
399
** routine returns SQLITE_ABORT without invoking the callback again and
400
** without running any subsequent SQL statements.
401
**
402
** ^The 2nd argument to the sqlite3_exec() callback function is the
403
** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
404
** callback is an array of pointers to strings obtained as if from
405
** [sqlite3_column_text()], one for each column. ^If an element of a
406
** result row is NULL then the corresponding string pointer for the
407
** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
408
** sqlite3_exec() callback is an array of pointers to strings where each
409
** entry represents the name of a corresponding result column as obtained
410
** from [sqlite3_column_name()].
411
**
412
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
413
** to an empty string, or a pointer that contains only whitespace and/or
414
** SQL comments, then no SQL statements are evaluated and the database
415
** is not changed.
416
**
417
** Restrictions:
418
**
419
** <ul>
420
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
421
** is a valid and open [database connection].
422
** <li> The application must not close the [database connection] specified by
423
** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
424
** <li> The application must not modify the SQL statement text passed into
425
** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
426
** <li> The application must not dereference the arrays or string pointers
427
** passed as the 3rd and 4th callback parameters after it returns.
428
** </ul>
429
*/
430
SQLITE_API int sqlite3_exec(
431
sqlite3*, /* An open database */
432
const char *sql, /* SQL to be evaluated */
433
int (*callback)(void*,int,char**,char**), /* Callback function */
434
void *, /* 1st argument to callback */
435
char **errmsg /* Error msg written here */
436
);
437
438
/*
439
** CAPI3REF: Result Codes
440
** KEYWORDS: {result code definitions}
441
**
442
** Many SQLite functions return an integer result code from the set shown
443
** here in order to indicate success or failure.
444
**
445
** New error codes may be added in future versions of SQLite.
446
**
447
** See also: [extended result code definitions]
448
*/
449
#define SQLITE_OK 0 /* Successful result */
450
/* beginning-of-error-codes */
451
#define SQLITE_ERROR 1 /* Generic error */
452
#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
453
#define SQLITE_PERM 3 /* Access permission denied */
454
#define SQLITE_ABORT 4 /* Callback routine requested an abort */
455
#define SQLITE_BUSY 5 /* The database file is locked */
456
#define SQLITE_LOCKED 6 /* A table in the database is locked */
457
#define SQLITE_NOMEM 7 /* A malloc() failed */
458
#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
459
#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
460
#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
461
#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
462
#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
463
#define SQLITE_FULL 13 /* Insertion failed because database is full */
464
#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
465
#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
466
#define SQLITE_EMPTY 16 /* Internal use only */
467
#define SQLITE_SCHEMA 17 /* The database schema changed */
468
#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
469
#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
470
#define SQLITE_MISMATCH 20 /* Data type mismatch */
471
#define SQLITE_MISUSE 21 /* Library used incorrectly */
472
#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
473
#define SQLITE_AUTH 23 /* Authorization denied */
474
#define SQLITE_FORMAT 24 /* Not used */
475
#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
476
#define SQLITE_NOTADB 26 /* File opened that is not a database file */
477
#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */
478
#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */
479
#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
480
#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
481
/* end-of-error-codes */
482
483
/*
484
** CAPI3REF: Extended Result Codes
485
** KEYWORDS: {extended result code definitions}
486
**
487
** In its default configuration, SQLite API routines return one of 30 integer
488
** [result codes]. However, experience has shown that many of
489
** these result codes are too coarse-grained. They do not provide as
490
** much information about problems as programmers might like. In an effort to
491
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
492
** and later) include
493
** support for additional result codes that provide more detailed information
494
** about errors. These [extended result codes] are enabled or disabled
495
** on a per database connection basis using the
496
** [sqlite3_extended_result_codes()] API. Or, the extended code for
497
** the most recent error can be obtained using
498
** [sqlite3_extended_errcode()].
499
*/
500
#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8))
501
#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8))
502
#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8))
503
#define SQLITE_ERROR_RESERVESIZE (SQLITE_ERROR | (4<<8))
504
#define SQLITE_ERROR_KEY (SQLITE_ERROR | (5<<8))
505
#define SQLITE_ERROR_UNABLE (SQLITE_ERROR | (6<<8))
506
#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
507
#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
508
#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
509
#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
510
#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
511
#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
512
#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
513
#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
514
#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
515
#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
516
#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
517
#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
518
#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
519
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
520
#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
521
#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
522
#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
523
#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
524
#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
525
#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
526
#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
527
#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
528
#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))
529
#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))
530
#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))
531
#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))
532
#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))
533
#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))
534
#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8))
535
#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8))
536
#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8))
537
#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8))
538
#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8))
539
#define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8))
540
#define SQLITE_IOERR_BADKEY (SQLITE_IOERR | (35<<8))
541
#define SQLITE_IOERR_CODEC (SQLITE_IOERR | (36<<8))
542
#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
543
#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8))
544
#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
545
#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))
546
#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8))
547
#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
548
#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))
549
#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))
550
#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))
551
#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
552
#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8))
553
#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
554
#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8))
555
#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8))
556
#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
557
#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
558
#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))
559
#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))
560
#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8))
561
#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8))
562
#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))
563
#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))
564
#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))
565
#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))
566
#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))
567
#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))
568
#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))
569
#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))
570
#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))
571
#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))
572
#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))
573
#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8))
574
#define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8))
575
#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))
576
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
577
#define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8))
578
#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))
579
#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))
580
#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))
581
#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal only */
582
583
/*
584
** CAPI3REF: Flags For File Open Operations
585
**
586
** These bit values are intended for use in the
587
** 3rd parameter to the [sqlite3_open_v2()] interface and
588
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
589
**
590
** Only those flags marked as "Ok for sqlite3_open_v2()" may be
591
** used as the third argument to the [sqlite3_open_v2()] interface.
592
** The other flags have historically been ignored by sqlite3_open_v2(),
593
** though future versions of SQLite might change so that an error is
594
** raised if any of the disallowed bits are passed into sqlite3_open_v2().
595
** Applications should not depend on the historical behavior.
596
**
597
** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
598
** [sqlite3_open_v2()] does *not* cause the underlying database file
599
** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into
600
** [sqlite3_open_v2()] has historically been a no-op and might become an
601
** error in future versions of SQLite.
602
*/
603
#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
604
#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
605
#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
606
#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
607
#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
608
#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
609
#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
610
#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */
611
#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
612
#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
613
#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
614
#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
615
#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
616
#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
617
#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */
618
#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
619
#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
620
#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
621
#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
622
#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
623
#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */
624
#define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */
625
626
/* Reserved: 0x00F00000 */
627
/* Legacy compatibility: */
628
#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
629
630
631
/*
632
** CAPI3REF: Device Characteristics
633
**
634
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
635
** object returns an integer which is a vector of these
636
** bit values expressing I/O characteristics of the mass storage
637
** device that holds the file that the [sqlite3_io_methods]
638
** refers to.
639
**
640
** The SQLITE_IOCAP_ATOMIC property means that all writes of
641
** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
642
** mean that writes of blocks that are nnn bytes in size and
643
** are aligned to an address which is an integer multiple of
644
** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
645
** that when data is appended to a file, the data is appended
646
** first then the size of the file is extended, never the other
647
** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
648
** information is written to disk in the same order as calls
649
** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
650
** after reboot following a crash or power loss, the only bytes in a
651
** file that were written at the application level might have changed
652
** and that adjacent bytes, even bytes within the same sector are
653
** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
654
** flag indicates that a file cannot be deleted when open. The
655
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
656
** read-only media and cannot be changed even by processes with
657
** elevated privileges.
658
**
659
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
660
** filesystem supports doing multiple write operations atomically when those
661
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
662
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
663
**
664
** The SQLITE_IOCAP_SUBPAGE_READ property means that it is ok to read
665
** from the database file in amounts that are not a multiple of the
666
** page size and that do not begin at a page boundary. Without this
667
** property, SQLite is careful to only do full-page reads and write
668
** on aligned pages, with the one exception that it will do a sub-page
669
** read of the first page to access the database header.
670
*/
671
#define SQLITE_IOCAP_ATOMIC 0x00000001
672
#define SQLITE_IOCAP_ATOMIC512 0x00000002
673
#define SQLITE_IOCAP_ATOMIC1K 0x00000004
674
#define SQLITE_IOCAP_ATOMIC2K 0x00000008
675
#define SQLITE_IOCAP_ATOMIC4K 0x00000010
676
#define SQLITE_IOCAP_ATOMIC8K 0x00000020
677
#define SQLITE_IOCAP_ATOMIC16K 0x00000040
678
#define SQLITE_IOCAP_ATOMIC32K 0x00000080
679
#define SQLITE_IOCAP_ATOMIC64K 0x00000100
680
#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
681
#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
682
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
683
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
684
#define SQLITE_IOCAP_IMMUTABLE 0x00002000
685
#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000
686
#define SQLITE_IOCAP_SUBPAGE_READ 0x00008000
687
688
/*
689
** CAPI3REF: File Locking Levels
690
**
691
** SQLite uses one of these integer values as the second
692
** argument to calls it makes to the xLock() and xUnlock() methods
693
** of an [sqlite3_io_methods] object. These values are ordered from
694
** least restrictive to most restrictive.
695
**
696
** The argument to xLock() is always SHARED or higher. The argument to
697
** xUnlock is either SHARED or NONE.
698
*/
699
#define SQLITE_LOCK_NONE 0 /* xUnlock() only */
700
#define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */
701
#define SQLITE_LOCK_RESERVED 2 /* xLock() only */
702
#define SQLITE_LOCK_PENDING 3 /* xLock() only */
703
#define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */
704
705
/*
706
** CAPI3REF: Synchronization Type Flags
707
**
708
** When SQLite invokes the xSync() method of an
709
** [sqlite3_io_methods] object it uses a combination of
710
** these integer values as the second argument.
711
**
712
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
713
** sync operation only needs to flush data to mass storage. Inode
714
** information need not be flushed. If the lower four bits of the flag
715
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
716
** If the lower four bits equal SQLITE_SYNC_FULL, that means
717
** to use Mac OS X style fullsync instead of fsync().
718
**
719
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
720
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
721
** settings. The [synchronous pragma] determines when calls to the
722
** xSync VFS method occur and applies uniformly across all platforms.
723
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
724
** energetic or rigorous or forceful the sync operations are and
725
** only make a difference on Mac OSX for the default SQLite code.
726
** (Third-party VFS implementations might also make the distinction
727
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
728
** operating systems natively supported by SQLite, only Mac OSX
729
** cares about the difference.)
730
*/
731
#define SQLITE_SYNC_NORMAL 0x00002
732
#define SQLITE_SYNC_FULL 0x00003
733
#define SQLITE_SYNC_DATAONLY 0x00010
734
735
/*
736
** CAPI3REF: OS Interface Open File Handle
737
**
738
** An [sqlite3_file] object represents an open file in the
739
** [sqlite3_vfs | OS interface layer]. Individual OS interface
740
** implementations will
741
** want to subclass this object by appending additional fields
742
** for their own use. The pMethods entry is a pointer to an
743
** [sqlite3_io_methods] object that defines methods for performing
744
** I/O operations on the open file.
745
*/
746
typedef struct sqlite3_file sqlite3_file;
747
struct sqlite3_file {
748
const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
749
};
750
751
/*
752
** CAPI3REF: OS Interface File Virtual Methods Object
753
**
754
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
755
** [sqlite3_file] object (or, more commonly, a subclass of the
756
** [sqlite3_file] object) with a pointer to an instance of this object.
757
** This object defines the methods used to perform various operations
758
** against the open file represented by the [sqlite3_file] object.
759
**
760
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
761
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
762
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
763
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
764
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
765
** to NULL.
766
**
767
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
768
** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
769
** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
770
** flag may be ORed in to indicate that only the data of the file
771
** and not its inode needs to be synced.
772
**
773
** The integer values to xLock() and xUnlock() are one of
774
** <ul>
775
** <li> [SQLITE_LOCK_NONE],
776
** <li> [SQLITE_LOCK_SHARED],
777
** <li> [SQLITE_LOCK_RESERVED],
778
** <li> [SQLITE_LOCK_PENDING], or
779
** <li> [SQLITE_LOCK_EXCLUSIVE].
780
** </ul>
781
** xLock() upgrades the database file lock. In other words, xLock() moves the
782
** database file lock in the direction NONE toward EXCLUSIVE. The argument to
783
** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
784
** SQLITE_LOCK_NONE. If the database file lock is already at or above the
785
** requested lock, then the call to xLock() is a no-op.
786
** xUnlock() downgrades the database file lock to either SHARED or NONE.
787
** If the lock is already at or below the requested lock state, then the call
788
** to xUnlock() is a no-op.
789
** The xCheckReservedLock() method checks whether any database connection,
790
** either in this process or in some other process, is holding a RESERVED,
791
** PENDING, or EXCLUSIVE lock on the file. It returns, via its output
792
** pointer parameter, true if such a lock exists and false otherwise.
793
**
794
** The xFileControl() method is a generic interface that allows custom
795
** VFS implementations to directly control an open file using the
796
** [sqlite3_file_control()] interface. The second "op" argument is an
797
** integer opcode. The third argument is a generic pointer intended to
798
** point to a structure that may contain arguments or space in which to
799
** write return values. Potential uses for xFileControl() might be
800
** functions to enable blocking locks with timeouts, to change the
801
** locking strategy (for example to use dot-file locks), to inquire
802
** about the status of a lock, or to break stale locks. The SQLite
803
** core reserves all opcodes less than 100 for its own use.
804
** A [file control opcodes | list of opcodes] less than 100 is available.
805
** Applications that define a custom xFileControl method should use opcodes
806
** greater than 100 to avoid conflicts. VFS implementations should
807
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
808
** recognize.
809
**
810
** The xSectorSize() method returns the sector size of the
811
** device that underlies the file. The sector size is the
812
** minimum write that can be performed without disturbing
813
** other bytes in the file. The xDeviceCharacteristics()
814
** method returns a bit vector describing behaviors of the
815
** underlying device:
816
**
817
** <ul>
818
** <li> [SQLITE_IOCAP_ATOMIC]
819
** <li> [SQLITE_IOCAP_ATOMIC512]
820
** <li> [SQLITE_IOCAP_ATOMIC1K]
821
** <li> [SQLITE_IOCAP_ATOMIC2K]
822
** <li> [SQLITE_IOCAP_ATOMIC4K]
823
** <li> [SQLITE_IOCAP_ATOMIC8K]
824
** <li> [SQLITE_IOCAP_ATOMIC16K]
825
** <li> [SQLITE_IOCAP_ATOMIC32K]
826
** <li> [SQLITE_IOCAP_ATOMIC64K]
827
** <li> [SQLITE_IOCAP_SAFE_APPEND]
828
** <li> [SQLITE_IOCAP_SEQUENTIAL]
829
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
830
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
831
** <li> [SQLITE_IOCAP_IMMUTABLE]
832
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
833
** <li> [SQLITE_IOCAP_SUBPAGE_READ]
834
** </ul>
835
**
836
** The SQLITE_IOCAP_ATOMIC property means that all writes of
837
** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
838
** mean that writes of blocks that are nnn bytes in size and
839
** are aligned to an address which is an integer multiple of
840
** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
841
** that when data is appended to a file, the data is appended
842
** first then the size of the file is extended, never the other
843
** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
844
** information is written to disk in the same order as calls
845
** to xWrite().
846
**
847
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
848
** in the unread portions of the buffer with zeros. A VFS that
849
** fails to zero-fill short reads might seem to work. However,
850
** failure to zero-fill short reads will eventually lead to
851
** database corruption.
852
*/
853
typedef struct sqlite3_io_methods sqlite3_io_methods;
854
struct sqlite3_io_methods {
855
int iVersion;
856
int (*xClose)(sqlite3_file*);
857
int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
858
int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
859
int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
860
int (*xSync)(sqlite3_file*, int flags);
861
int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
862
int (*xLock)(sqlite3_file*, int);
863
int (*xUnlock)(sqlite3_file*, int);
864
int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
865
int (*xFileControl)(sqlite3_file*, int op, void *pArg);
866
int (*xSectorSize)(sqlite3_file*);
867
int (*xDeviceCharacteristics)(sqlite3_file*);
868
/* Methods above are valid for version 1 */
869
int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
870
int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
871
void (*xShmBarrier)(sqlite3_file*);
872
int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
873
/* Methods above are valid for version 2 */
874
int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
875
int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
876
/* Methods above are valid for version 3 */
877
/* Additional methods may be added in future releases */
878
};
879
880
/*
881
** CAPI3REF: Standard File Control Opcodes
882
** KEYWORDS: {file control opcodes} {file control opcode}
883
**
884
** These integer constants are opcodes for the xFileControl method
885
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
886
** interface.
887
**
888
** <ul>
889
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
890
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
891
** opcode causes the xFileControl method to write the current state of
892
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
893
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
894
** into an integer that the pArg argument points to.
895
** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].
896
**
897
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
898
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
899
** layer a hint of how large the database file will grow to be during the
900
** current transaction. This hint is not guaranteed to be accurate but it
901
** is often close. The underlying VFS might choose to preallocate database
902
** file space based on this hint in order to help writes to the database
903
** file run faster.
904
**
905
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
906
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
907
** implements [sqlite3_deserialize()] to set an upper bound on the size
908
** of the in-memory database. The argument is a pointer to a [sqlite3_int64].
909
** If the integer pointed to is negative, then it is filled in with the
910
** current limit. Otherwise the limit is set to the larger of the value
911
** of the integer pointed to and the current database size. The integer
912
** pointed to is set to the new limit.
913
**
914
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
915
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
916
** extends and truncates the database file in chunks of a size specified
917
** by the user. The fourth argument to [sqlite3_file_control()] should
918
** point to an integer (type int) containing the new chunk-size to use
919
** for the nominated database. Allocating database file space in large
920
** chunks (say 1MB at a time), may reduce file-system fragmentation and
921
** improve performance on some systems.
922
**
923
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
924
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
925
** to the [sqlite3_file] object associated with a particular database
926
** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].
927
**
928
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
929
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
930
** to the [sqlite3_file] object associated with the journal file (either
931
** the [rollback journal] or the [write-ahead log]) for a particular database
932
** connection. See also [SQLITE_FCNTL_FILE_POINTER].
933
**
934
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
935
** The SQLITE_FCNTL_SYNC_OMITTED file-control is no longer used.
936
**
937
** <li>[[SQLITE_FCNTL_SYNC]]
938
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
939
** sent to the VFS immediately before the xSync method is invoked on a
940
** database file descriptor. Or, if the xSync method is not invoked
941
** because the user has configured SQLite with
942
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
943
** of the xSync method. In most cases, the pointer argument passed with
944
** this file-control is NULL. However, if the database file is being synced
945
** as part of a multi-database commit, the argument points to a nul-terminated
946
** string containing the transactions super-journal file name. VFSes that
947
** do not need this signal should silently ignore this opcode. Applications
948
** should not call [sqlite3_file_control()] with this opcode as doing so may
949
** disrupt the operation of the specialized VFSes that do require it.
950
**
951
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
952
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
953
** and sent to the VFS after a transaction has been committed immediately
954
** but before the database is unlocked. VFSes that do not need this signal
955
** should silently ignore this opcode. Applications should not call
956
** [sqlite3_file_control()] with this opcode as doing so may disrupt the
957
** operation of the specialized VFSes that do require it.
958
**
959
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
960
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
961
** retry counts and intervals for certain disk I/O operations for the
962
** windows [VFS] in order to provide robustness in the presence of
963
** anti-virus programs. By default, the windows VFS will retry file read,
964
** file write, and file delete operations up to 10 times, with a delay
965
** of 25 milliseconds before the first retry and with the delay increasing
966
** by an additional 25 milliseconds with each subsequent retry. This
967
** opcode allows these two values (10 retries and 25 milliseconds of delay)
968
** to be adjusted. The values are changed for all database connections
969
** within the same process. The argument is a pointer to an array of two
970
** integers where the first integer is the new retry count and the second
971
** integer is the delay. If either integer is negative, then the setting
972
** is not changed but instead the prior value of that setting is written
973
** into the array entry, allowing the current retry settings to be
974
** interrogated. The zDbName parameter is ignored.
975
**
976
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
977
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
978
** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary
979
** write ahead log ([WAL file]) and shared memory
980
** files used for transaction control
981
** are automatically deleted when the latest connection to the database
982
** closes. Setting persistent WAL mode causes those files to persist after
983
** close. Persisting the files is useful when other processes that do not
984
** have write permission on the directory containing the database file want
985
** to read the database file, as the WAL and shared memory files must exist
986
** in order for the database to be readable. The fourth parameter to
987
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
988
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
989
** WAL mode. If the integer is -1, then it is overwritten with the current
990
** WAL persistence setting.
991
**
992
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
993
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
994
** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
995
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
996
** xDeviceCharacteristics methods. The fourth parameter to
997
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
998
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
999
** mode. If the integer is -1, then it is overwritten with the current
1000
** zero-damage mode setting.
1001
**
1002
** <li>[[SQLITE_FCNTL_OVERWRITE]]
1003
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
1004
** a write transaction to indicate that, unless it is rolled back for some
1005
** reason, the entire database file will be overwritten by the current
1006
** transaction. This is used by VACUUM operations.
1007
**
1008
** <li>[[SQLITE_FCNTL_VFSNAME]]
1009
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1010
** all [VFSes] in the VFS stack. The names of all VFS shims and the
1011
** final bottom-level VFS are written into memory obtained from
1012
** [sqlite3_malloc()] and the result is stored in the char* variable
1013
** that the fourth parameter of [sqlite3_file_control()] points to.
1014
** The caller is responsible for freeing the memory when done. As with
1015
** all file-control actions, there is no guarantee that this will actually
1016
** do anything. Callers should initialize the char* variable to a NULL
1017
** pointer in case this file-control is not implemented. This file-control
1018
** is intended for diagnostic use only.
1019
**
1020
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
1021
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
1022
** [VFSes] currently in use. ^(The argument X in
1023
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
1024
** of type "[sqlite3_vfs] **". This opcode will set *X
1025
** to a pointer to the top-level VFS.)^
1026
** ^When there are multiple VFS shims in the stack, this opcode finds the
1027
** upper-most shim only.
1028
**
1029
** <li>[[SQLITE_FCNTL_PRAGMA]]
1030
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1031
** file control is sent to the open [sqlite3_file] object corresponding
1032
** to the database file to which the pragma statement refers. ^The argument
1033
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1034
** pointers to strings (char**) in which the second element of the array
1035
** is the name of the pragma and the third element is the argument to the
1036
** pragma or NULL if the pragma has no argument. ^The handler for an
1037
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1038
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1039
** or the equivalent and that string will become the result of the pragma or
1040
** the error message if the pragma fails. ^If the
1041
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1042
** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]
1043
** file control returns [SQLITE_OK], then the parser assumes that the
1044
** VFS has handled the PRAGMA itself and the parser generates a no-op
1045
** prepared statement if result string is NULL, or that returns a copy
1046
** of the result string if the string is non-NULL.
1047
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1048
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1049
** that the VFS encountered an error while handling the [PRAGMA] and the
1050
** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]
1051
** file control occurs at the beginning of pragma statement analysis and so
1052
** it is able to override built-in [PRAGMA] statements.
1053
**
1054
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1055
** ^The [SQLITE_FCNTL_BUSYHANDLER]
1056
** file-control may be invoked by SQLite on the database file handle
1057
** shortly after it is opened in order to provide a custom VFS with access
1058
** to the connection's busy-handler callback. The argument is of type (void**)
1059
** - an array of two (void *) values. The first (void *) actually points
1060
** to a function of type (int (*)(void *)). In order to invoke the connection's
1061
** busy-handler, this function should be invoked with the second (void *) in
1062
** the array as the only argument. If it returns non-zero, then the operation
1063
** should be retried. If it returns zero, the custom VFS should abandon the
1064
** current operation.
1065
**
1066
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1067
** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1068
** to have SQLite generate a
1069
** temporary filename using the same algorithm that is followed to generate
1070
** temporary filenames for TEMP tables and other internal uses. The
1071
** argument should be a char** which will be filled with the filename
1072
** written into memory obtained from [sqlite3_malloc()]. The caller should
1073
** invoke [sqlite3_free()] on the result to avoid a memory leak.
1074
**
1075
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1076
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1077
** maximum number of bytes that will be used for memory-mapped I/O.
1078
** The argument is a pointer to a value of type sqlite3_int64 that
1079
** is an advisory maximum number of bytes in the file to memory map. The
1080
** pointer is overwritten with the old value. The limit is not changed if
1081
** the value originally pointed to is negative, and so the current limit
1082
** can be queried by passing in a pointer to a negative number. This
1083
** file-control is used internally to implement [PRAGMA mmap_size].
1084
**
1085
** <li>[[SQLITE_FCNTL_TRACE]]
1086
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1087
** to the VFS about what the higher layers of the SQLite stack are doing.
1088
** This file control is used by some VFS activity tracing [shims].
1089
** The argument is a zero-terminated string. Higher layers in the
1090
** SQLite stack may generate instances of this file control if
1091
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1092
**
1093
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1094
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1095
** pointer to an integer and it writes a boolean into that integer depending
1096
** on whether or not the file has been renamed, moved, or deleted since it
1097
** was first opened.
1098
**
1099
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1100
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1101
** underlying native file handle associated with a file handle. This file
1102
** control interprets its argument as a pointer to a native file handle and
1103
** writes the resulting value there.
1104
**
1105
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1106
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This
1107
** opcode causes the xFileControl method to swap the file handle with the one
1108
** pointed to by the pArg argument. This capability is used during testing
1109
** and only needs to be supported when SQLITE_TEST is defined.
1110
**
1111
** <li>[[SQLITE_FCNTL_NULL_IO]]
1112
** The [SQLITE_FCNTL_NULL_IO] opcode sets the low-level file descriptor
1113
** or file handle for the [sqlite3_file] object such that it will no longer
1114
** read or write to the database file.
1115
**
1116
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1117
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1118
** be advantageous to block on the next WAL lock if the lock is not immediately
1119
** available. The WAL subsystem issues this signal during rare
1120
** circumstances in order to fix a problem with priority inversion.
1121
** Applications should <em>not</em> use this file-control.
1122
**
1123
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1124
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1125
** VFS should return SQLITE_NOTFOUND for this opcode.
1126
**
1127
** <li>[[SQLITE_FCNTL_RBU]]
1128
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1129
** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for
1130
** this opcode.
1131
**
1132
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1133
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1134
** the file descriptor is placed in "batch write mode", which
1135
** means all subsequent write operations will be deferred and done
1136
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems
1137
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1138
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1139
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1140
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1141
** no VFS interface calls on the same [sqlite3_file] file descriptor
1142
** except for calls to the xWrite method and the xFileControl method
1143
** with [SQLITE_FCNTL_SIZE_HINT].
1144
**
1145
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1146
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1147
** operations since the previous successful call to
1148
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1149
** This file control returns [SQLITE_OK] if and only if the writes were
1150
** all performed successfully and have been committed to persistent storage.
1151
** ^Regardless of whether or not it is successful, this file control takes
1152
** the file descriptor out of batch write mode so that all subsequent
1153
** write operations are independent.
1154
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1155
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1156
**
1157
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1158
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1159
** operations since the previous successful call to
1160
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1161
** ^This file control takes the file descriptor out of batch write mode
1162
** so that all subsequent write operations are independent.
1163
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1164
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1165
**
1166
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1167
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1168
** to block for up to M milliseconds before failing when attempting to
1169
** obtain a file lock using the xLock or xShmLock methods of the VFS.
1170
** The parameter is a pointer to a 32-bit signed integer that contains
1171
** the value that M is to be set to. Before returning, the 32-bit signed
1172
** integer is overwritten with the previous value of M.
1173
**
1174
** <li>[[SQLITE_FCNTL_BLOCK_ON_CONNECT]]
1175
** The [SQLITE_FCNTL_BLOCK_ON_CONNECT] opcode is used to configure the
1176
** VFS to block when taking a SHARED lock to connect to a wal mode database.
1177
** This is used to implement the functionality associated with
1178
** SQLITE_SETLK_BLOCK_ON_CONNECT.
1179
**
1180
** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1181
** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1182
** a database file. The argument is a pointer to a 32-bit unsigned integer.
1183
** The "data version" for the pager is written into the pointer. The
1184
** "data version" changes whenever any change occurs to the corresponding
1185
** database file, either through SQL statements on the same database
1186
** connection or through transactions committed by separate database
1187
** connections possibly in other processes. The [sqlite3_total_changes()]
1188
** interface can be used to find if any database on the connection has changed,
1189
** but that interface responds to changes on TEMP as well as MAIN and does
1190
** not provide a mechanism to detect changes to MAIN only. Also, the
1191
** [sqlite3_total_changes()] interface responds to internal changes only and
1192
** omits changes made by other database connections. The
1193
** [PRAGMA data_version] command provides a mechanism to detect changes to
1194
** a single attached database that occur due to other database connections,
1195
** but omits changes implemented by the database connection on which it is
1196
** called. This file control is the only mechanism to detect changes that
1197
** happen either internally or externally and that are associated with
1198
** a particular attached database.
1199
**
1200
** <li>[[SQLITE_FCNTL_CKPT_START]]
1201
** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1202
** in wal mode before the client starts to copy pages from the wal
1203
** file to the database file.
1204
**
1205
** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1206
** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1207
** in wal mode after the client has finished copying pages from the wal
1208
** file to the database file, but before the *-shm file is updated to
1209
** record the fact that the pages have been checkpointed.
1210
**
1211
** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1212
** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1213
** whether or not there is a database client in another process with a wal-mode
1214
** transaction open on the database or not. It is only available on unix. The
1215
** (void*) argument passed with this file-control should be a pointer to a
1216
** value of type (int). The integer value is set to 1 if the database is a wal
1217
** mode database and there exists at least one client in another process that
1218
** currently has an SQL transaction open on the database. It is set to 0 if
1219
** the database is not a wal-mode db, or if there is no such connection in any
1220
** other process. This opcode cannot be used to detect transactions opened
1221
** by clients within the current process, only within other processes.
1222
**
1223
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1224
** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the
1225
** [checksum VFS shim] only.
1226
**
1227
** <li>[[SQLITE_FCNTL_RESET_CACHE]]
1228
** If there is currently no transaction open on the database, and the
1229
** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control
1230
** purges the contents of the in-memory page cache. If there is an open
1231
** transaction, or if the db is a temp-db, this opcode is a no-op, not an error.
1232
**
1233
** <li>[[SQLITE_FCNTL_FILESTAT]]
1234
** The [SQLITE_FCNTL_FILESTAT] opcode returns low-level diagnostic information
1235
** about the [sqlite3_file] objects used access the database and journal files
1236
** for the given schema. The fourth parameter to [sqlite3_file_control()]
1237
** should be an initialized [sqlite3_str] pointer. JSON text describing
1238
** various aspects of the sqlite3_file object is appended to the sqlite3_str.
1239
** The SQLITE_FCNTL_FILESTAT opcode is usually a no-op, unless compile-time
1240
** options are used to enable it.
1241
** </ul>
1242
*/
1243
#define SQLITE_FCNTL_LOCKSTATE 1
1244
#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2
1245
#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3
1246
#define SQLITE_FCNTL_LAST_ERRNO 4
1247
#define SQLITE_FCNTL_SIZE_HINT 5
1248
#define SQLITE_FCNTL_CHUNK_SIZE 6
1249
#define SQLITE_FCNTL_FILE_POINTER 7
1250
#define SQLITE_FCNTL_SYNC_OMITTED 8
1251
#define SQLITE_FCNTL_WIN32_AV_RETRY 9
1252
#define SQLITE_FCNTL_PERSIST_WAL 10
1253
#define SQLITE_FCNTL_OVERWRITE 11
1254
#define SQLITE_FCNTL_VFSNAME 12
1255
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
1256
#define SQLITE_FCNTL_PRAGMA 14
1257
#define SQLITE_FCNTL_BUSYHANDLER 15
1258
#define SQLITE_FCNTL_TEMPFILENAME 16
1259
#define SQLITE_FCNTL_MMAP_SIZE 18
1260
#define SQLITE_FCNTL_TRACE 19
1261
#define SQLITE_FCNTL_HAS_MOVED 20
1262
#define SQLITE_FCNTL_SYNC 21
1263
#define SQLITE_FCNTL_COMMIT_PHASETWO 22
1264
#define SQLITE_FCNTL_WIN32_SET_HANDLE 23
1265
#define SQLITE_FCNTL_WAL_BLOCK 24
1266
#define SQLITE_FCNTL_ZIPVFS 25
1267
#define SQLITE_FCNTL_RBU 26
1268
#define SQLITE_FCNTL_VFS_POINTER 27
1269
#define SQLITE_FCNTL_JOURNAL_POINTER 28
1270
#define SQLITE_FCNTL_WIN32_GET_HANDLE 29
1271
#define SQLITE_FCNTL_PDB 30
1272
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31
1273
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32
1274
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33
1275
#define SQLITE_FCNTL_LOCK_TIMEOUT 34
1276
#define SQLITE_FCNTL_DATA_VERSION 35
1277
#define SQLITE_FCNTL_SIZE_LIMIT 36
1278
#define SQLITE_FCNTL_CKPT_DONE 37
1279
#define SQLITE_FCNTL_RESERVE_BYTES 38
1280
#define SQLITE_FCNTL_CKPT_START 39
1281
#define SQLITE_FCNTL_EXTERNAL_READER 40
1282
#define SQLITE_FCNTL_CKSM_FILE 41
1283
#define SQLITE_FCNTL_RESET_CACHE 42
1284
#define SQLITE_FCNTL_NULL_IO 43
1285
#define SQLITE_FCNTL_BLOCK_ON_CONNECT 44
1286
#define SQLITE_FCNTL_FILESTAT 45
1287
1288
/* deprecated names */
1289
#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE
1290
#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE
1291
#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO
1292
1293
/* reserved file-control numbers:
1294
** 101
1295
** 102
1296
** 103
1297
*/
1298
1299
1300
/*
1301
** CAPI3REF: Mutex Handle
1302
**
1303
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1304
** abstract type for a mutex object. The SQLite core never looks
1305
** at the internal representation of an [sqlite3_mutex]. It only
1306
** deals with pointers to the [sqlite3_mutex] object.
1307
**
1308
** Mutexes are created using [sqlite3_mutex_alloc()].
1309
*/
1310
typedef struct sqlite3_mutex sqlite3_mutex;
1311
1312
/*
1313
** CAPI3REF: Loadable Extension Thunk
1314
**
1315
** A pointer to the opaque sqlite3_api_routines structure is passed as
1316
** the third parameter to entry points of [loadable extensions]. This
1317
** structure must be typedefed in order to work around compiler warnings
1318
** on some platforms.
1319
*/
1320
typedef struct sqlite3_api_routines sqlite3_api_routines;
1321
1322
/*
1323
** CAPI3REF: File Name
1324
**
1325
** Type [sqlite3_filename] is used by SQLite to pass filenames to the
1326
** xOpen method of a [VFS]. It may be cast to (const char*) and treated
1327
** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
1328
** may also be passed to special APIs such as:
1329
**
1330
** <ul>
1331
** <li> sqlite3_filename_database()
1332
** <li> sqlite3_filename_journal()
1333
** <li> sqlite3_filename_wal()
1334
** <li> sqlite3_uri_parameter()
1335
** <li> sqlite3_uri_boolean()
1336
** <li> sqlite3_uri_int64()
1337
** <li> sqlite3_uri_key()
1338
** </ul>
1339
*/
1340
typedef const char *sqlite3_filename;
1341
1342
/*
1343
** CAPI3REF: OS Interface Object
1344
**
1345
** An instance of the sqlite3_vfs object defines the interface between
1346
** the SQLite core and the underlying operating system. The "vfs"
1347
** in the name of the object stands for "virtual file system". See
1348
** the [VFS | VFS documentation] for further information.
1349
**
1350
** The VFS interface is sometimes extended by adding new methods onto
1351
** the end. Each time such an extension occurs, the iVersion field
1352
** is incremented. The iVersion value started out as 1 in
1353
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1354
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1355
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields
1356
** may be appended to the sqlite3_vfs object and the iVersion value
1357
** may increase again in future versions of SQLite.
1358
** Note that due to an oversight, the structure
1359
** of the sqlite3_vfs object changed in the transition from
1360
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1361
** and yet the iVersion field was not increased.
1362
**
1363
** The szOsFile field is the size of the subclassed [sqlite3_file]
1364
** structure used by this VFS. mxPathname is the maximum length of
1365
** a pathname in this VFS.
1366
**
1367
** Registered sqlite3_vfs objects are kept on a linked list formed by
1368
** the pNext pointer. The [sqlite3_vfs_register()]
1369
** and [sqlite3_vfs_unregister()] interfaces manage this list
1370
** in a thread-safe way. The [sqlite3_vfs_find()] interface
1371
** searches the list. Neither the application code nor the VFS
1372
** implementation should use the pNext pointer.
1373
**
1374
** The pNext field is the only field in the sqlite3_vfs
1375
** structure that SQLite will ever modify. SQLite will only access
1376
** or modify this field while holding a particular static mutex.
1377
** The application should never modify anything within the sqlite3_vfs
1378
** object once the object has been registered.
1379
**
1380
** The zName field holds the name of the VFS module. The name must
1381
** be unique across all VFS modules.
1382
**
1383
** [[sqlite3_vfs.xOpen]]
1384
** ^SQLite guarantees that the zFilename parameter to xOpen
1385
** is either a NULL pointer or string obtained
1386
** from xFullPathname() with an optional suffix added.
1387
** ^If a suffix is added to the zFilename parameter, it will
1388
** consist of a single "-" character followed by no more than
1389
** 11 alphanumeric and/or "-" characters.
1390
** ^SQLite further guarantees that
1391
** the string will be valid and unchanged until xClose() is
1392
** called. Because of the previous sentence,
1393
** the [sqlite3_file] can safely store a pointer to the
1394
** filename if it needs to remember the filename for some reason.
1395
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1396
** must invent its own temporary name for the file. ^Whenever the
1397
** xFilename parameter is NULL it will also be the case that the
1398
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1399
**
1400
** The flags argument to xOpen() includes all bits set in
1401
** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
1402
** or [sqlite3_open16()] is used, then flags includes at least
1403
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1404
** If xOpen() opens a file read-only then it sets *pOutFlags to
1405
** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
1406
**
1407
** ^(SQLite will also add one of the following flags to the xOpen()
1408
** call, depending on the object being opened:
1409
**
1410
** <ul>
1411
** <li> [SQLITE_OPEN_MAIN_DB]
1412
** <li> [SQLITE_OPEN_MAIN_JOURNAL]
1413
** <li> [SQLITE_OPEN_TEMP_DB]
1414
** <li> [SQLITE_OPEN_TEMP_JOURNAL]
1415
** <li> [SQLITE_OPEN_TRANSIENT_DB]
1416
** <li> [SQLITE_OPEN_SUBJOURNAL]
1417
** <li> [SQLITE_OPEN_SUPER_JOURNAL]
1418
** <li> [SQLITE_OPEN_WAL]
1419
** </ul>)^
1420
**
1421
** The file I/O implementation can use the object type flags to
1422
** change the way it deals with files. For example, an application
1423
** that does not care about crash recovery or rollback might make
1424
** the open of a journal file a no-op. Writes to this journal would
1425
** also be no-ops, and any attempt to read the journal would return
1426
** SQLITE_IOERR. Or the implementation might recognize that a database
1427
** file will be doing page-aligned sector reads and writes in a random
1428
** order and set up its I/O subsystem accordingly.
1429
**
1430
** SQLite might also add one of the following flags to the xOpen method:
1431
**
1432
** <ul>
1433
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1434
** <li> [SQLITE_OPEN_EXCLUSIVE]
1435
** </ul>
1436
**
1437
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1438
** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
1439
** will be set for TEMP databases and their journals, transient
1440
** databases, and subjournals.
1441
**
1442
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1443
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1444
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1445
** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1446
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1447
** be created, and that it is an error if it already exists.
1448
** It is <i>not</i> used to indicate the file should be opened
1449
** for exclusive access.
1450
**
1451
** ^At least szOsFile bytes of memory are allocated by SQLite
1452
** to hold the [sqlite3_file] structure passed as the third
1453
** argument to xOpen. The xOpen method does not have to
1454
** allocate the structure; it should just fill it in. Note that
1455
** the xOpen method must set the sqlite3_file.pMethods to either
1456
** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
1457
** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
1458
** element will be valid after xOpen returns regardless of the success
1459
** or failure of the xOpen call.
1460
**
1461
** [[sqlite3_vfs.xAccess]]
1462
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1463
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1464
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1465
** to test whether a file is at least readable. The SQLITE_ACCESS_READ
1466
** flag is never actually used and is not implemented in the built-in
1467
** VFSes of SQLite. The file is named by the second argument and can be a
1468
** directory. The xAccess method returns [SQLITE_OK] on success or some
1469
** non-zero error code if there is an I/O error or if the name of
1470
** the file given in the second argument is illegal. If SQLITE_OK
1471
** is returned, then non-zero or zero is written into *pResOut to indicate
1472
** whether or not the file is accessible.
1473
**
1474
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1475
** output buffer xFullPathname. The exact size of the output buffer
1476
** is also passed as a parameter to both methods. If the output buffer
1477
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1478
** handled as a fatal error by SQLite, vfs implementations should endeavor
1479
** to prevent this by setting mxPathname to a sufficiently large value.
1480
**
1481
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1482
** interfaces are not strictly a part of the filesystem, but they are
1483
** included in the VFS structure for completeness.
1484
** The xRandomness() function attempts to return nBytes bytes
1485
** of good-quality randomness into zOut. The return value is
1486
** the actual number of bytes of randomness obtained.
1487
** The xSleep() method causes the calling thread to sleep for at
1488
** least the number of microseconds given. ^The xCurrentTime()
1489
** method returns a Julian Day Number for the current date and time as
1490
** a floating point value.
1491
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1492
** Day Number multiplied by 86400000 (the number of milliseconds in
1493
** a 24-hour day).
1494
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1495
** date and time if that method is available (if iVersion is 2 or
1496
** greater and the function pointer is not NULL) and will fall back
1497
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1498
**
1499
** ^The xSetSystemCall(), xGetSystemCall(), and xNextSystemCall() interfaces
1500
** are not used by the SQLite core. These optional interfaces are provided
1501
** by some VFSes to facilitate testing of the VFS code. By overriding
1502
** system calls with functions under its control, a test program can
1503
** simulate faults and error conditions that would otherwise be difficult
1504
** or impossible to induce. The set of system calls that can be overridden
1505
** varies from one VFS to another, and from one version of the same VFS to the
1506
** next. Applications that use these interfaces must be prepared for any
1507
** or all of these interfaces to be NULL or for their behavior to change
1508
** from one release to the next. Applications must not attempt to access
1509
** any of these methods if the iVersion of the VFS is less than 3.
1510
*/
1511
typedef struct sqlite3_vfs sqlite3_vfs;
1512
typedef void (*sqlite3_syscall_ptr)(void);
1513
struct sqlite3_vfs {
1514
int iVersion; /* Structure version number (currently 3) */
1515
int szOsFile; /* Size of subclassed sqlite3_file */
1516
int mxPathname; /* Maximum file pathname length */
1517
sqlite3_vfs *pNext; /* Next registered VFS */
1518
const char *zName; /* Name of this virtual file system */
1519
void *pAppData; /* Pointer to application-specific data */
1520
int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
1521
int flags, int *pOutFlags);
1522
int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1523
int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1524
int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1525
void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1526
void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1527
void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1528
void (*xDlClose)(sqlite3_vfs*, void*);
1529
int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1530
int (*xSleep)(sqlite3_vfs*, int microseconds);
1531
int (*xCurrentTime)(sqlite3_vfs*, double*);
1532
int (*xGetLastError)(sqlite3_vfs*, int, char *);
1533
/*
1534
** The methods above are in version 1 of the sqlite_vfs object
1535
** definition. Those that follow are added in version 2 or later
1536
*/
1537
int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1538
/*
1539
** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1540
** Those below are for version 3 and greater.
1541
*/
1542
int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1543
sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1544
const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1545
/*
1546
** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1547
** New fields may be appended in future versions. The iVersion
1548
** value will increment whenever this happens.
1549
*/
1550
};
1551
1552
/*
1553
** CAPI3REF: Flags for the xAccess VFS method
1554
**
1555
** These integer constants can be used as the third parameter to
1556
** the xAccess method of an [sqlite3_vfs] object. They determine
1557
** what kind of permissions the xAccess method is looking for.
1558
** With SQLITE_ACCESS_EXISTS, the xAccess method
1559
** simply checks whether the file exists.
1560
** With SQLITE_ACCESS_READWRITE, the xAccess method
1561
** checks whether the named directory is both readable and writable
1562
** (in other words, if files can be added, removed, and renamed within
1563
** the directory).
1564
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1565
** [temp_store_directory pragma], though this could change in a future
1566
** release of SQLite.
1567
** With SQLITE_ACCESS_READ, the xAccess method
1568
** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
1569
** currently unused, though it might be used in a future release of
1570
** SQLite.
1571
*/
1572
#define SQLITE_ACCESS_EXISTS 0
1573
#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
1574
#define SQLITE_ACCESS_READ 2 /* Unused */
1575
1576
/*
1577
** CAPI3REF: Flags for the xShmLock VFS method
1578
**
1579
** These integer constants define the various locking operations
1580
** allowed by the xShmLock method of [sqlite3_io_methods]. The
1581
** following are the only legal combinations of flags to the
1582
** xShmLock method:
1583
**
1584
** <ul>
1585
** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1586
** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1587
** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1588
** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1589
** </ul>
1590
**
1591
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1592
** was given on the corresponding lock.
1593
**
1594
** The xShmLock method can transition between unlocked and SHARED or
1595
** between unlocked and EXCLUSIVE. It cannot transition between SHARED
1596
** and EXCLUSIVE.
1597
*/
1598
#define SQLITE_SHM_UNLOCK 1
1599
#define SQLITE_SHM_LOCK 2
1600
#define SQLITE_SHM_SHARED 4
1601
#define SQLITE_SHM_EXCLUSIVE 8
1602
1603
/*
1604
** CAPI3REF: Maximum xShmLock index
1605
**
1606
** The xShmLock method on [sqlite3_io_methods] may use values
1607
** between 0 and this upper bound as its "offset" argument.
1608
** The SQLite core will never attempt to acquire or release a
1609
** lock outside of this range
1610
*/
1611
#define SQLITE_SHM_NLOCK 8
1612
1613
1614
/*
1615
** CAPI3REF: Initialize The SQLite Library
1616
**
1617
** ^The sqlite3_initialize() routine initializes the
1618
** SQLite library. ^The sqlite3_shutdown() routine
1619
** deallocates any resources that were allocated by sqlite3_initialize().
1620
** These routines are designed to aid in process initialization and
1621
** shutdown on embedded systems. Workstation applications using
1622
** SQLite normally do not need to invoke either of these routines.
1623
**
1624
** A call to sqlite3_initialize() is an "effective" call if it is
1625
** the first time sqlite3_initialize() is invoked during the lifetime of
1626
** the process, or if it is the first time sqlite3_initialize() is invoked
1627
** following a call to sqlite3_shutdown(). ^(Only an effective call
1628
** of sqlite3_initialize() does any initialization. All other calls
1629
** are harmless no-ops.)^
1630
**
1631
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1632
** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
1633
** an effective call to sqlite3_shutdown() does any deinitialization.
1634
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1635
**
1636
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1637
** is not. The sqlite3_shutdown() interface must only be called from a
1638
** single thread. All open [database connections] must be closed and all
1639
** other SQLite resources must be deallocated prior to invoking
1640
** sqlite3_shutdown().
1641
**
1642
** Among other things, ^sqlite3_initialize() will invoke
1643
** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
1644
** will invoke sqlite3_os_end().
1645
**
1646
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1647
** ^If for some reason, sqlite3_initialize() is unable to initialize
1648
** the library (perhaps it is unable to allocate a needed resource such
1649
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1650
**
1651
** ^The sqlite3_initialize() routine is called internally by many other
1652
** SQLite interfaces so that an application usually does not need to
1653
** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
1654
** calls sqlite3_initialize() so the SQLite library will be automatically
1655
** initialized when [sqlite3_open()] is called if it has not been initialized
1656
** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1657
** compile-time option, then the automatic calls to sqlite3_initialize()
1658
** are omitted and the application must call sqlite3_initialize() directly
1659
** prior to using any other SQLite interface. For maximum portability,
1660
** it is recommended that applications always invoke sqlite3_initialize()
1661
** directly prior to using any other SQLite interface. Future releases
1662
** of SQLite may require this. In other words, the behavior exhibited
1663
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1664
** default behavior in some future release of SQLite.
1665
**
1666
** The sqlite3_os_init() routine does operating-system specific
1667
** initialization of the SQLite library. The sqlite3_os_end()
1668
** routine undoes the effect of sqlite3_os_init(). Typical tasks
1669
** performed by these routines include allocation or deallocation
1670
** of static resources, initialization of global variables,
1671
** setting up a default [sqlite3_vfs] module, or setting up
1672
** a default configuration using [sqlite3_config()].
1673
**
1674
** The application should never invoke either sqlite3_os_init()
1675
** or sqlite3_os_end() directly. The application should only invoke
1676
** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
1677
** interface is called automatically by sqlite3_initialize() and
1678
** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
1679
** implementations for sqlite3_os_init() and sqlite3_os_end()
1680
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1681
** When [custom builds | built for other platforms]
1682
** (using the [SQLITE_OS_OTHER=1] compile-time
1683
** option) the application must supply a suitable implementation for
1684
** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1685
** implementation of sqlite3_os_init() or sqlite3_os_end()
1686
** must return [SQLITE_OK] on success and some other [error code] upon
1687
** failure.
1688
*/
1689
SQLITE_API int sqlite3_initialize(void);
1690
SQLITE_API int sqlite3_shutdown(void);
1691
SQLITE_API int sqlite3_os_init(void);
1692
SQLITE_API int sqlite3_os_end(void);
1693
1694
/*
1695
** CAPI3REF: Configuring The SQLite Library
1696
**
1697
** The sqlite3_config() interface is used to make global configuration
1698
** changes to SQLite in order to tune SQLite to the specific needs of
1699
** the application. The default configuration is recommended for most
1700
** applications and so this routine is usually not necessary. It is
1701
** provided to support rare applications with unusual needs.
1702
**
1703
** <b>The sqlite3_config() interface is not threadsafe. The application
1704
** must ensure that no other SQLite interfaces are invoked by other
1705
** threads while sqlite3_config() is running.</b>
1706
**
1707
** The first argument to sqlite3_config() is an integer
1708
** [configuration option] that determines
1709
** what property of SQLite is to be configured. Subsequent arguments
1710
** vary depending on the [configuration option]
1711
** in the first argument.
1712
**
1713
** For most configuration options, the sqlite3_config() interface
1714
** may only be invoked prior to library initialization using
1715
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1716
** The exceptional configuration options that may be invoked at any time
1717
** are called "anytime configuration options".
1718
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1719
** [sqlite3_shutdown()] with a first argument that is not an anytime
1720
** configuration option, then the sqlite3_config() call will
1721
** return SQLITE_MISUSE.
1722
** Note, however, that ^sqlite3_config() can be called as part of the
1723
** implementation of an application-defined [sqlite3_os_init()].
1724
**
1725
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1726
** ^If the option is unknown or SQLite is unable to set the option
1727
** then this routine returns a non-zero [error code].
1728
*/
1729
SQLITE_API int sqlite3_config(int, ...);
1730
1731
/*
1732
** CAPI3REF: Configure database connections
1733
** METHOD: sqlite3
1734
**
1735
** The sqlite3_db_config() interface is used to make configuration
1736
** changes to a [database connection]. The interface is similar to
1737
** [sqlite3_config()] except that the changes apply to a single
1738
** [database connection] (specified in the first argument).
1739
**
1740
** The second argument to sqlite3_db_config(D,V,...) is the
1741
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1742
** that indicates what aspect of the [database connection] is being configured.
1743
** Subsequent arguments vary depending on the configuration verb.
1744
**
1745
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1746
** the call is considered successful.
1747
*/
1748
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1749
1750
/*
1751
** CAPI3REF: Memory Allocation Routines
1752
**
1753
** An instance of this object defines the interface between SQLite
1754
** and low-level memory allocation routines.
1755
**
1756
** This object is used in only one place in the SQLite interface.
1757
** A pointer to an instance of this object is the argument to
1758
** [sqlite3_config()] when the configuration option is
1759
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1760
** By creating an instance of this object
1761
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1762
** during configuration, an application can specify an alternative
1763
** memory allocation subsystem for SQLite to use for all of its
1764
** dynamic memory needs.
1765
**
1766
** Note that SQLite comes with several [built-in memory allocators]
1767
** that are perfectly adequate for the overwhelming majority of applications
1768
** and that this object is only useful to a tiny minority of applications
1769
** with specialized memory allocation requirements. This object is
1770
** also used during testing of SQLite in order to specify an alternative
1771
** memory allocator that simulates memory out-of-memory conditions in
1772
** order to verify that SQLite recovers gracefully from such
1773
** conditions.
1774
**
1775
** The xMalloc, xRealloc, and xFree methods must work like the
1776
** malloc(), realloc() and free() functions from the standard C library.
1777
** ^SQLite guarantees that the second argument to
1778
** xRealloc is always a value returned by a prior call to xRoundup.
1779
**
1780
** xSize should return the allocated size of a memory allocation
1781
** previously obtained from xMalloc or xRealloc. The allocated size
1782
** is always at least as big as the requested size but may be larger.
1783
**
1784
** The xRoundup method returns what would be the allocated size of
1785
** a memory allocation given a particular requested size. Most memory
1786
** allocators round up memory allocations at least to the next multiple
1787
** of 8. Some allocators round up to a larger multiple or to a power of 2.
1788
** Every memory allocation request coming in through [sqlite3_malloc()]
1789
** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1790
** that causes the corresponding memory allocation to fail.
1791
**
1792
** The xInit method initializes the memory allocator. For example,
1793
** it might allocate any required mutexes or initialize internal data
1794
** structures. The xShutdown method is invoked (indirectly) by
1795
** [sqlite3_shutdown()] and should deallocate any resources acquired
1796
** by xInit. The pAppData pointer is used as the only parameter to
1797
** xInit and xShutdown.
1798
**
1799
** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1800
** the xInit method, so the xInit method need not be threadsafe. The
1801
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1802
** not need to be threadsafe either. For all other methods, SQLite
1803
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1804
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1805
** it is by default) and so the methods are automatically serialized.
1806
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1807
** methods must be threadsafe or else make their own arrangements for
1808
** serialization.
1809
**
1810
** SQLite will never invoke xInit() more than once without an intervening
1811
** call to xShutdown().
1812
*/
1813
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1814
struct sqlite3_mem_methods {
1815
void *(*xMalloc)(int); /* Memory allocation function */
1816
void (*xFree)(void*); /* Free a prior allocation */
1817
void *(*xRealloc)(void*,int); /* Resize an allocation */
1818
int (*xSize)(void*); /* Return the size of an allocation */
1819
int (*xRoundup)(int); /* Round up request size to allocation size */
1820
int (*xInit)(void*); /* Initialize the memory allocator */
1821
void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1822
void *pAppData; /* Argument to xInit() and xShutdown() */
1823
};
1824
1825
/*
1826
** CAPI3REF: Configuration Options
1827
** KEYWORDS: {configuration option}
1828
**
1829
** These constants are the available integer configuration options that
1830
** can be passed as the first argument to the [sqlite3_config()] interface.
1831
**
1832
** Most of the configuration options for sqlite3_config()
1833
** will only work if invoked prior to [sqlite3_initialize()] or after
1834
** [sqlite3_shutdown()]. The few exceptions to this rule are called
1835
** "anytime configuration options".
1836
** ^Calling [sqlite3_config()] with a first argument that is not an
1837
** anytime configuration option in between calls to [sqlite3_initialize()] and
1838
** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
1839
**
1840
** The set of anytime configuration options can change (by insertions
1841
** and/or deletions) from one release of SQLite to the next.
1842
** As of SQLite version 3.42.0, the complete set of anytime configuration
1843
** options is:
1844
** <ul>
1845
** <li> SQLITE_CONFIG_LOG
1846
** <li> SQLITE_CONFIG_PCACHE_HDRSZ
1847
** </ul>
1848
**
1849
** New configuration options may be added in future releases of SQLite.
1850
** Existing configuration options might be discontinued. Applications
1851
** should check the return code from [sqlite3_config()] to make sure that
1852
** the call worked. The [sqlite3_config()] interface will return a
1853
** non-zero [error code] if a discontinued or unsupported configuration option
1854
** is invoked.
1855
**
1856
** <dl>
1857
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1858
** <dd>There are no arguments to this option. ^This option sets the
1859
** [threading mode] to Single-thread. In other words, it disables
1860
** all mutexing and puts SQLite into a mode where it can only be used
1861
** by a single thread. ^If SQLite is compiled with
1862
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1863
** it is not possible to change the [threading mode] from its default
1864
** value of Single-thread and so [sqlite3_config()] will return
1865
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1866
** configuration option.</dd>
1867
**
1868
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1869
** <dd>There are no arguments to this option. ^This option sets the
1870
** [threading mode] to Multi-thread. In other words, it disables
1871
** mutexing on [database connection] and [prepared statement] objects.
1872
** The application is responsible for serializing access to
1873
** [database connections] and [prepared statements]. But other mutexes
1874
** are enabled so that SQLite will be safe to use in a multi-threaded
1875
** environment as long as no two threads attempt to use the same
1876
** [database connection] at the same time. ^If SQLite is compiled with
1877
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1878
** it is not possible to set the Multi-thread [threading mode] and
1879
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1880
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1881
**
1882
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1883
** <dd>There are no arguments to this option. ^This option sets the
1884
** [threading mode] to Serialized. In other words, this option enables
1885
** all mutexes including the recursive
1886
** mutexes on [database connection] and [prepared statement] objects.
1887
** In this mode (which is the default when SQLite is compiled with
1888
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1889
** to [database connections] and [prepared statements] so that the
1890
** application is free to use the same [database connection] or the
1891
** same [prepared statement] in different threads at the same time.
1892
** ^If SQLite is compiled with
1893
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1894
** it is not possible to set the Serialized [threading mode] and
1895
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1896
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1897
**
1898
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1899
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1900
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1901
** The argument specifies
1902
** alternative low-level memory allocation routines to be used in place of
1903
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1904
** its own private copy of the content of the [sqlite3_mem_methods] structure
1905
** before the [sqlite3_config()] call returns.</dd>
1906
**
1907
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1908
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1909
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1910
** The [sqlite3_mem_methods]
1911
** structure is filled with the currently defined memory allocation routines.)^
1912
** This option can be used to overload the default memory allocation
1913
** routines with a wrapper that simulates memory allocation failure or
1914
** tracks memory usage, for example. </dd>
1915
**
1916
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1917
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes a single argument of
1918
** type int, interpreted as a boolean, which if true provides a hint to
1919
** SQLite that it should avoid large memory allocations if possible.
1920
** SQLite will run faster if it is free to make large memory allocations,
1921
** but some applications might prefer to run slower in exchange for
1922
** guarantees about memory fragmentation that are possible if large
1923
** allocations are avoided. This hint is normally off.
1924
** </dd>
1925
**
1926
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1927
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes a single argument of type int,
1928
** interpreted as a boolean, which enables or disables the collection of
1929
** memory allocation statistics. ^(When memory allocation statistics are
1930
** disabled, the following SQLite interfaces become non-operational:
1931
** <ul>
1932
** <li> [sqlite3_hard_heap_limit64()]
1933
** <li> [sqlite3_memory_used()]
1934
** <li> [sqlite3_memory_highwater()]
1935
** <li> [sqlite3_soft_heap_limit64()]
1936
** <li> [sqlite3_status64()]
1937
** </ul>)^
1938
** ^Memory allocation statistics are enabled by default unless SQLite is
1939
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1940
** allocation statistics are disabled by default.
1941
** </dd>
1942
**
1943
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1944
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1945
** </dd>
1946
**
1947
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1948
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1949
** that SQLite can use for the database page cache with the default page
1950
** cache implementation.
1951
** This configuration option is a no-op if an application-defined page
1952
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1953
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1954
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1955
** and the number of cache lines (N).
1956
** The sz argument should be the size of the largest database page
1957
** (a power of two between 512 and 65536) plus some extra bytes for each
1958
** page header. ^The number of extra bytes needed by the page header
1959
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1960
** ^It is harmless, apart from the wasted memory,
1961
** for the sz parameter to be larger than necessary. The pMem
1962
** argument must be either a NULL pointer or a pointer to an 8-byte
1963
** aligned block of memory of at least sz*N bytes, otherwise
1964
** subsequent behavior is undefined.
1965
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1966
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1967
** a page cache line is larger than sz bytes or if all of the pMem buffer
1968
** is exhausted.
1969
** ^If pMem is NULL and N is non-zero, then each database connection
1970
** does an initial bulk allocation for page cache memory
1971
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1972
** of -1024*N bytes if N is negative. ^If additional
1973
** page cache memory is needed beyond what is provided by the initial
1974
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1975
** additional cache line. </dd>
1976
**
1977
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1978
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1979
** that SQLite will use for all of its dynamic memory allocation needs
1980
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1981
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1982
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1983
** [SQLITE_ERROR] if invoked otherwise.
1984
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1985
** An 8-byte aligned pointer to the memory,
1986
** the number of bytes in the memory buffer, and the minimum allocation size.
1987
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1988
** to using its default memory allocator (the system malloc() implementation),
1989
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
1990
** memory pointer is not NULL then the alternative memory
1991
** allocator is engaged to handle all of SQLites memory allocation needs.
1992
** The first pointer (the memory pointer) must be aligned to an 8-byte
1993
** boundary or subsequent behavior of SQLite will be undefined.
1994
** The minimum allocation size is capped at 2**12. Reasonable values
1995
** for the minimum allocation size are 2**5 through 2**8.</dd>
1996
**
1997
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1998
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1999
** pointer to an instance of the [sqlite3_mutex_methods] structure.
2000
** The argument specifies alternative low-level mutex routines to be used
2001
** in place of the mutex routines built into SQLite.)^ ^SQLite makes a copy of
2002
** the content of the [sqlite3_mutex_methods] structure before the call to
2003
** [sqlite3_config()] returns. ^If SQLite is compiled with
2004
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2005
** the entire mutexing subsystem is omitted from the build and hence calls to
2006
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
2007
** return [SQLITE_ERROR].</dd>
2008
**
2009
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
2010
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
2011
** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The
2012
** [sqlite3_mutex_methods]
2013
** structure is filled with the currently defined mutex routines.)^
2014
** This option can be used to overload the default mutex allocation
2015
** routines with a wrapper used to track mutex usage for performance
2016
** profiling or testing, for example. ^If SQLite is compiled with
2017
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
2018
** the entire mutexing subsystem is omitted from the build and hence calls to
2019
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
2020
** return [SQLITE_ERROR].</dd>
2021
**
2022
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
2023
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
2024
** the default size of [lookaside memory] on each [database connection].
2025
** The first argument is the
2026
** size of each lookaside buffer slot ("sz") and the second is the number of
2027
** slots allocated to each database connection ("cnt").)^
2028
** ^(SQLITE_CONFIG_LOOKASIDE sets the <i>default</i> lookaside size.
2029
** The [SQLITE_DBCONFIG_LOOKASIDE] option to [sqlite3_db_config()] can
2030
** be used to change the lookaside configuration on individual connections.)^
2031
** The [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to change the
2032
** default lookaside configuration at compile-time.
2033
** </dd>
2034
**
2035
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
2036
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
2037
** a pointer to an [sqlite3_pcache_methods2] object. This object specifies
2038
** the interface to a custom page cache implementation.)^
2039
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
2040
**
2041
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
2042
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
2043
** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies off
2044
** the current page cache implementation into that object.)^ </dd>
2045
**
2046
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
2047
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
2048
** global [error log].
2049
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
2050
** function with a call signature of void(*)(void*,int,const char*),
2051
** and a pointer to void. ^If the function pointer is not NULL, it is
2052
** invoked by [sqlite3_log()] to process each logging event. ^If the
2053
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
2054
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
2055
** passed through as the first parameter to the application-defined logger
2056
** function whenever that function is invoked. ^The second parameter to
2057
** the logger function is a copy of the first parameter to the corresponding
2058
** [sqlite3_log()] call and is intended to be a [result code] or an
2059
** [extended result code]. ^The third parameter passed to the logger is
2060
** a log message after formatting via [sqlite3_snprintf()].
2061
** The SQLite logging interface is not reentrant; the logger function
2062
** supplied by the application must not invoke any SQLite interface.
2063
** In a multi-threaded application, the application-defined logger
2064
** function must be threadsafe. </dd>
2065
**
2066
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
2067
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
2068
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
2069
** then URI handling is globally disabled.)^ ^If URI handling is globally
2070
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
2071
** [sqlite3_open16()] or
2072
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
2073
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
2074
** connection is opened. ^If it is globally disabled, filenames are
2075
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
2076
** database connection is opened. ^(By default, URI handling is globally
2077
** disabled. The default value may be changed by compiling with the
2078
** [SQLITE_USE_URI] symbol defined.)^
2079
**
2080
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
2081
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
2082
** argument which is interpreted as a boolean in order to enable or disable
2083
** the use of covering indices for full table scans in the query optimizer.
2084
** ^The default setting is determined
2085
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
2086
** if that compile-time option is omitted.
2087
** The ability to disable the use of covering indices for full table scans
2088
** is because some incorrectly coded legacy applications might malfunction
2089
** when the optimization is enabled. Providing the ability to
2090
** disable the optimization allows the older, buggy application code to work
2091
** without change even with newer versions of SQLite.
2092
**
2093
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
2094
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
2095
** <dd> These options are obsolete and should not be used by new code.
2096
** They are retained for backwards compatibility but are now no-ops.
2097
** </dd>
2098
**
2099
** [[SQLITE_CONFIG_SQLLOG]]
2100
** <dt>SQLITE_CONFIG_SQLLOG
2101
** <dd>This option is only available if sqlite is compiled with the
2102
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
2103
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
2104
** The second should be of type (void*). The callback is invoked by the library
2105
** in three separate circumstances, identified by the value passed as the
2106
** fourth parameter. If the fourth parameter is 0, then the database connection
2107
** passed as the second argument has just been opened. The third argument
2108
** points to a buffer containing the name of the main database file. If the
2109
** fourth parameter is 1, then the SQL statement that the third parameter
2110
** points to has just been executed. Or, if the fourth parameter is 2, then
2111
** the connection being passed as the second parameter is being closed. The
2112
** third parameter is passed NULL In this case. An example of using this
2113
** configuration option can be seen in the "test_sqllog.c" source file in
2114
** the canonical SQLite source tree.</dd>
2115
**
2116
** [[SQLITE_CONFIG_MMAP_SIZE]]
2117
** <dt>SQLITE_CONFIG_MMAP_SIZE
2118
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2119
** that are the default mmap size limit (the default setting for
2120
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2121
** ^The default setting can be overridden by each database connection using
2122
** either the [PRAGMA mmap_size] command, or by using the
2123
** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size
2124
** will be silently truncated if necessary so that it does not exceed the
2125
** compile-time maximum mmap size set by the
2126
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2127
** ^If either argument to this option is negative, then that argument is
2128
** changed to its compile-time default.
2129
**
2130
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2131
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2132
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2133
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2134
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2135
** that specifies the maximum size of the created heap.
2136
**
2137
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2138
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2139
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2140
** is a pointer to an integer and writes into that integer the number of extra
2141
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2142
** The amount of extra space required can change depending on the compiler,
2143
** target platform, and SQLite version.
2144
**
2145
** [[SQLITE_CONFIG_PMASZ]]
2146
** <dt>SQLITE_CONFIG_PMASZ
2147
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2148
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2149
** sorter to that integer. The default minimum PMA Size is set by the
2150
** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched
2151
** to help with sort operations when multithreaded sorting
2152
** is enabled (using the [PRAGMA threads] command) and the amount of content
2153
** to be sorted exceeds the page size times the minimum of the
2154
** [PRAGMA cache_size] setting and this value.
2155
**
2156
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2157
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2158
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2159
** becomes the [statement journal] spill-to-disk threshold.
2160
** [Statement journals] are held in memory until their size (in bytes)
2161
** exceeds this threshold, at which point they are written to disk.
2162
** Or if the threshold is -1, statement journals are always held
2163
** exclusively in memory.
2164
** Since many statement journals never become large, setting the spill
2165
** threshold to a value such as 64KiB can greatly reduce the amount of
2166
** I/O required to support statement rollback.
2167
** The default value for this setting is controlled by the
2168
** [SQLITE_STMTJRNL_SPILL] compile-time option.
2169
**
2170
** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2171
** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2172
** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2173
** of type (int) - the new value of the sorter-reference size threshold.
2174
** Usually, when SQLite uses an external sort to order records according
2175
** to an ORDER BY clause, all fields required by the caller are present in the
2176
** sorted records. However, if SQLite determines based on the declared type
2177
** of a table column that its values are likely to be very large - larger
2178
** than the configured sorter-reference size threshold - then a reference
2179
** is stored in each sorted record and the required column values loaded
2180
** from the database as records are returned in sorted order. The default
2181
** value for this option is to never use this optimization. Specifying a
2182
** negative value for this option restores the default behavior.
2183
** This option is only available if SQLite is compiled with the
2184
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2185
**
2186
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2187
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2188
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2189
** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2190
** database created using [sqlite3_deserialize()]. This default maximum
2191
** size can be adjusted up or down for individual databases using the
2192
** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this
2193
** configuration setting is never used, then the default maximum is determined
2194
** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that
2195
** compile-time option is not set, then the default maximum is 1073741824.
2196
**
2197
** [[SQLITE_CONFIG_ROWID_IN_VIEW]]
2198
** <dt>SQLITE_CONFIG_ROWID_IN_VIEW
2199
** <dd>The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability
2200
** for VIEWs to have a ROWID. The capability can only be enabled if SQLite is
2201
** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability
2202
** defaults to on. This configuration option queries the current setting or
2203
** changes the setting to off or on. The argument is a pointer to an integer.
2204
** If that integer initially holds a value of 1, then the ability for VIEWs to
2205
** have ROWIDs is activated. If the integer initially holds zero, then the
2206
** ability is deactivated. Any other initial value for the integer leaves the
2207
** setting unchanged. After changes, if any, the integer is written with
2208
** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off. If SQLite
2209
** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and
2210
** recommended case) then the integer is always filled with zero, regardless
2211
** if its initial value.
2212
** </dl>
2213
*/
2214
#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
2215
#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
2216
#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
2217
#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
2218
#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
2219
#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */
2220
#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
2221
#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
2222
#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
2223
#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
2224
#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
2225
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
2226
#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
2227
#define SQLITE_CONFIG_PCACHE 14 /* no-op */
2228
#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
2229
#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
2230
#define SQLITE_CONFIG_URI 17 /* int */
2231
#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
2232
#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
2233
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */
2234
#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */
2235
#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */
2236
#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */
2237
#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */
2238
#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */
2239
#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */
2240
#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */
2241
#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */
2242
#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */
2243
#define SQLITE_CONFIG_ROWID_IN_VIEW 30 /* int* */
2244
2245
/*
2246
** CAPI3REF: Database Connection Configuration Options
2247
**
2248
** These constants are the available integer configuration options that
2249
** can be passed as the second parameter to the [sqlite3_db_config()] interface.
2250
**
2251
** The [sqlite3_db_config()] interface is a var-args function. It takes a
2252
** variable number of parameters, though always at least two. The number of
2253
** parameters passed into sqlite3_db_config() depends on which of these
2254
** constants is given as the second parameter. This documentation page
2255
** refers to parameters beyond the second as "arguments". Thus, when this
2256
** page says "the N-th argument" it means "the N-th parameter past the
2257
** configuration option" or "the (N+2)-th parameter to sqlite3_db_config()".
2258
**
2259
** New configuration options may be added in future releases of SQLite.
2260
** Existing configuration options might be discontinued. Applications
2261
** should check the return code from [sqlite3_db_config()] to make sure that
2262
** the call worked. ^The [sqlite3_db_config()] interface will return a
2263
** non-zero [error code] if a discontinued or unsupported configuration option
2264
** is invoked.
2265
**
2266
** <dl>
2267
** [[SQLITE_DBCONFIG_LOOKASIDE]]
2268
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2269
** <dd> The SQLITE_DBCONFIG_LOOKASIDE option is used to adjust the
2270
** configuration of the [lookaside memory allocator] within a database
2271
** connection.
2272
** The arguments to the SQLITE_DBCONFIG_LOOKASIDE option are <i>not</i>
2273
** in the [DBCONFIG arguments|usual format].
2274
** The SQLITE_DBCONFIG_LOOKASIDE option takes three arguments, not two,
2275
** so that a call to [sqlite3_db_config()] that uses SQLITE_DBCONFIG_LOOKASIDE
2276
** should have a total of five parameters.
2277
** <ol>
2278
** <li><p>The first argument ("buf") is a
2279
** pointer to a memory buffer to use for lookaside memory.
2280
** The first argument may be NULL in which case SQLite will allocate the
2281
** lookaside buffer itself using [sqlite3_malloc()].
2282
** <li><P>The second argument ("sz") is the
2283
** size of each lookaside buffer slot. Lookaside is disabled if "sz"
2284
** is less than 8. The "sz" argument should be a multiple of 8 less than
2285
** 65536. If "sz" does not meet this constraint, it is reduced in size until
2286
** it does.
2287
** <li><p>The third argument ("cnt") is the number of slots.
2288
** Lookaside is disabled if "cnt"is less than 1.
2289
* The "cnt" value will be reduced, if necessary, so
2290
** that the product of "sz" and "cnt" does not exceed 2,147,418,112. The "cnt"
2291
** parameter is usually chosen so that the product of "sz" and "cnt" is less
2292
** than 1,000,000.
2293
** </ol>
2294
** <p>If the "buf" argument is not NULL, then it must
2295
** point to a memory buffer with a size that is greater than
2296
** or equal to the product of "sz" and "cnt".
2297
** The buffer must be aligned to an 8-byte boundary.
2298
** The lookaside memory
2299
** configuration for a database connection can only be changed when that
2300
** connection is not currently using lookaside memory, or in other words
2301
** when the value returned by [SQLITE_DBSTATUS_LOOKASIDE_USED] is zero.
2302
** Any attempt to change the lookaside memory configuration when lookaside
2303
** memory is in use leaves the configuration unchanged and returns
2304
** [SQLITE_BUSY].
2305
** If the "buf" argument is NULL and an attempt
2306
** to allocate memory based on "sz" and "cnt" fails, then
2307
** lookaside is silently disabled.
2308
** <p>
2309
** The [SQLITE_CONFIG_LOOKASIDE] configuration option can be used to set the
2310
** default lookaside configuration at initialization. The
2311
** [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to set the default lookaside
2312
** configuration at compile-time. Typical values for lookaside are 1200 for
2313
** "sz" and 40 to 100 for "cnt".
2314
** </dd>
2315
**
2316
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2317
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2318
** <dd> ^This option is used to enable or disable the enforcement of
2319
** [foreign key constraints]. This is the same setting that is
2320
** enabled or disabled by the [PRAGMA foreign_keys] statement.
2321
** The first argument is an integer which is 0 to disable FK enforcement,
2322
** positive to enable FK enforcement or negative to leave FK enforcement
2323
** unchanged. The second parameter is a pointer to an integer into which
2324
** is written 0 or 1 to indicate whether FK enforcement is off or on
2325
** following this call. The second parameter may be a NULL pointer, in
2326
** which case the FK enforcement setting is not reported back. </dd>
2327
**
2328
** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2329
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2330
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2331
** There should be two additional arguments.
2332
** The first argument is an integer which is 0 to disable triggers,
2333
** positive to enable triggers or negative to leave the setting unchanged.
2334
** The second parameter is a pointer to an integer into which
2335
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2336
** following this call. The second parameter may be a NULL pointer, in
2337
** which case the trigger setting is not reported back.
2338
**
2339
** <p>Originally this option disabled all triggers. ^(However, since
2340
** SQLite version 3.35.0, TEMP triggers are still allowed even if
2341
** this option is off. So, in other words, this option now only disables
2342
** triggers in the main database schema or in the schemas of [ATTACH]-ed
2343
** databases.)^ </dd>
2344
**
2345
** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2346
** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2347
** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2348
** There must be two additional arguments.
2349
** The first argument is an integer which is 0 to disable views,
2350
** positive to enable views or negative to leave the setting unchanged.
2351
** The second parameter is a pointer to an integer into which
2352
** is written 0 or 1 to indicate whether views are disabled or enabled
2353
** following this call. The second parameter may be a NULL pointer, in
2354
** which case the view setting is not reported back.
2355
**
2356
** <p>Originally this option disabled all views. ^(However, since
2357
** SQLite version 3.35.0, TEMP views are still allowed even if
2358
** this option is off. So, in other words, this option now only disables
2359
** views in the main database schema or in the schemas of ATTACH-ed
2360
** databases.)^ </dd>
2361
**
2362
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2363
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2364
** <dd> ^This option is used to enable or disable using the
2365
** [fts3_tokenizer()] function - part of the [FTS3] full-text search engine
2366
** extension - without using bound parameters as the parameters. Doing so
2367
** is disabled by default. There must be two additional arguments. The first
2368
** argument is an integer. If it is passed 0, then using fts3_tokenizer()
2369
** without bound parameters is disabled. If it is passed a positive value,
2370
** then calling fts3_tokenizer without bound parameters is enabled. If it
2371
** is passed a negative value, this setting is not modified - this can be
2372
** used to query for the current setting. The second parameter is a pointer
2373
** to an integer into which is written 0 or 1 to indicate the current value
2374
** of this setting (after it is modified, if applicable). The second
2375
** parameter may be a NULL pointer, in which case the value of the setting
2376
** is not reported back. Refer to [FTS3] documentation for further details.
2377
** </dd>
2378
**
2379
** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2380
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2381
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2382
** interface independently of the [load_extension()] SQL function.
2383
** The [sqlite3_enable_load_extension()] API enables or disables both the
2384
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2385
** There must be two additional arguments.
2386
** When the first argument to this interface is 1, then only the C-API is
2387
** enabled and the SQL function remains disabled. If the first argument to
2388
** this interface is 0, then both the C-API and the SQL function are disabled.
2389
** If the first argument is -1, then no changes are made to the state of either
2390
** the C-API or the SQL function.
2391
** The second parameter is a pointer to an integer into which
2392
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2393
** is disabled or enabled following this call. The second parameter may
2394
** be a NULL pointer, in which case the new setting is not reported back.
2395
** </dd>
2396
**
2397
** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2398
** <dd> ^This option is used to change the name of the "main" database
2399
** schema. This option does not follow the
2400
** [DBCONFIG arguments|usual SQLITE_DBCONFIG argument format].
2401
** This option takes exactly one additional argument so that the
2402
** [sqlite3_db_config()] call has a total of three parameters. The
2403
** extra argument must be a pointer to a constant UTF8 string which
2404
** will become the new schema name in place of "main". ^SQLite does
2405
** not make a copy of the new main schema name string, so the application
2406
** must ensure that the argument passed into SQLITE_DBCONFIG MAINDBNAME
2407
** is unchanged until after the database connection closes.
2408
** </dd>
2409
**
2410
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2411
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2412
** <dd> Usually, when a database in [WAL mode] is closed or detached from a
2413
** database handle, SQLite checks if if there are other connections to the
2414
** same database, and if there are no other database connection (if the
2415
** connection being closed is the last open connection to the database),
2416
** then SQLite performs a [checkpoint] before closing the connection and
2417
** deletes the WAL file. The SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE option can
2418
** be used to override that behavior. The first argument passed to this
2419
** operation (the third parameter to [sqlite3_db_config()]) is an integer
2420
** which is positive to disable checkpoints-on-close, or zero (the default)
2421
** to enable them, and negative to leave the setting unchanged.
2422
** The second argument (the fourth parameter) is a pointer to an integer
2423
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2424
** have been disabled - 0 if they are not disabled, 1 if they are.
2425
** </dd>
2426
**
2427
** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2428
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2429
** the [query planner stability guarantee] (QPSG). When the QPSG is active,
2430
** a single SQL query statement will always use the same algorithm regardless
2431
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2432
** that look at the values of bound parameters, which can make some queries
2433
** slower. But the QPSG has the advantage of more predictable behavior. With
2434
** the QPSG active, SQLite will always use the same query plan in the field as
2435
** was used during testing in the lab.
2436
** The first argument to this setting is an integer which is 0 to disable
2437
** the QPSG, positive to enable QPSG, or negative to leave the setting
2438
** unchanged. The second parameter is a pointer to an integer into which
2439
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2440
** following this call.
2441
** </dd>
2442
**
2443
** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2444
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2445
** include output for any operations performed by trigger programs. This
2446
** option is used to set or clear (the default) a flag that governs this
2447
** behavior. The first parameter passed to this operation is an integer -
2448
** positive to enable output for trigger programs, or zero to disable it,
2449
** or negative to leave the setting unchanged.
2450
** The second parameter is a pointer to an integer into which is written
2451
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2452
** it is not disabled, 1 if it is.
2453
** </dd>
2454
**
2455
** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2456
** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2457
** [VACUUM] in order to reset a database back to an empty database
2458
** with no schema and no content. The following process works even for
2459
** a badly corrupted database file:
2460
** <ol>
2461
** <li> If the database connection is newly opened, make sure it has read the
2462
** database schema by preparing then discarding some query against the
2463
** database, or calling sqlite3_table_column_metadata(), ignoring any
2464
** errors. This step is only necessary if the application desires to keep
2465
** the database in WAL mode after the reset if it was in WAL mode before
2466
** the reset.
2467
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2468
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2469
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2470
** </ol>
2471
** Because resetting a database is destructive and irreversible, the
2472
** process requires the use of this obscure API and multiple steps to
2473
** help ensure that it does not happen by accident. Because this
2474
** feature must be capable of resetting corrupt databases, and
2475
** shutting down virtual tables may require access to that corrupt
2476
** storage, the library must abandon any installed virtual tables
2477
** without calling their xDestroy() methods.
2478
**
2479
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2480
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2481
** "defensive" flag for a database connection. When the defensive
2482
** flag is enabled, language features that allow ordinary SQL to
2483
** deliberately corrupt the database file are disabled. The disabled
2484
** features include but are not limited to the following:
2485
** <ul>
2486
** <li> The [PRAGMA writable_schema=ON] statement.
2487
** <li> The [PRAGMA journal_mode=OFF] statement.
2488
** <li> The [PRAGMA schema_version=N] statement.
2489
** <li> Writes to the [sqlite_dbpage] virtual table.
2490
** <li> Direct writes to [shadow tables].
2491
** </ul>
2492
** </dd>
2493
**
2494
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2495
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2496
** "writable_schema" flag. This has the same effect and is logically equivalent
2497
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2498
** The first argument to this setting is an integer which is 0 to disable
2499
** the writable_schema, positive to enable writable_schema, or negative to
2500
** leave the setting unchanged. The second parameter is a pointer to an
2501
** integer into which is written 0 or 1 to indicate whether the writable_schema
2502
** is enabled or disabled following this call.
2503
** </dd>
2504
**
2505
** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2506
** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2507
** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2508
** the legacy behavior of the [ALTER TABLE RENAME] command such that it
2509
** behaves as it did prior to [version 3.24.0] (2018-06-04). See the
2510
** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2511
** additional information. This feature can also be turned on and off
2512
** using the [PRAGMA legacy_alter_table] statement.
2513
** </dd>
2514
**
2515
** [[SQLITE_DBCONFIG_DQS_DML]]
2516
** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
2517
** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2518
** the legacy [double-quoted string literal] misfeature for DML statements
2519
** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2520
** default value of this setting is determined by the [-DSQLITE_DQS]
2521
** compile-time option.
2522
** </dd>
2523
**
2524
** [[SQLITE_DBCONFIG_DQS_DDL]]
2525
** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
2526
** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2527
** the legacy [double-quoted string literal] misfeature for DDL statements,
2528
** such as CREATE TABLE and CREATE INDEX. The
2529
** default value of this setting is determined by the [-DSQLITE_DQS]
2530
** compile-time option.
2531
** </dd>
2532
**
2533
** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2534
** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
2535
** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2536
** assume that database schemas are untainted by malicious content.
2537
** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2538
** takes additional defensive steps to protect the application from harm
2539
** including:
2540
** <ul>
2541
** <li> Prohibit the use of SQL functions inside triggers, views,
2542
** CHECK constraints, DEFAULT clauses, expression indexes,
2543
** partial indexes, or generated columns
2544
** unless those functions are tagged with [SQLITE_INNOCUOUS].
2545
** <li> Prohibit the use of virtual tables inside of triggers or views
2546
** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2547
** </ul>
2548
** This setting defaults to "on" for legacy compatibility, however
2549
** all applications are advised to turn it off if possible. This setting
2550
** can also be controlled using the [PRAGMA trusted_schema] statement.
2551
** </dd>
2552
**
2553
** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2554
** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
2555
** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2556
** the legacy file format flag. When activated, this flag causes all newly
2557
** created database files to have a schema format version number (the 4-byte
2558
** integer found at offset 44 into the database header) of 1. This in turn
2559
** means that the resulting database file will be readable and writable by
2560
** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting,
2561
** newly created databases are generally not understandable by SQLite versions
2562
** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there
2563
** is now scarcely any need to generate database files that are compatible
2564
** all the way back to version 3.0.0, and so this setting is of little
2565
** practical use, but is provided so that SQLite can continue to claim the
2566
** ability to generate new database files that are compatible with version
2567
** 3.0.0.
2568
** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2569
** the [VACUUM] command will fail with an obscure error when attempting to
2570
** process a table with generated columns and a descending index. This is
2571
** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2572
** either generated columns or descending indexes.
2573
** </dd>
2574
**
2575
** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
2576
** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
2577
** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
2578
** [SQLITE_ENABLE_STMT_SCANSTATUS] builds. In this case, it sets or clears
2579
** a flag that enables collection of run-time performance statistics
2580
** used by [sqlite3_stmt_scanstatus_v2()] and the [nexec and ncycle]
2581
** columns of the [bytecode virtual table].
2582
** For statistics to be collected, the flag must be set on
2583
** the database handle both when the SQL statement is
2584
** [sqlite3_prepare|prepared] and when it is [sqlite3_step|stepped].
2585
** The flag is set (collection of statistics is enabled) by default.
2586
** <p>This option takes two arguments: an integer and a pointer to
2587
** an integer. The first argument is 1, 0, or -1 to enable, disable, or
2588
** leave unchanged the statement scanstatus option. If the second argument
2589
** is not NULL, then the value of the statement scanstatus setting after
2590
** processing the first argument is written into the integer that the second
2591
** argument points to.
2592
** </dd>
2593
**
2594
** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
2595
** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
2596
** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
2597
** in which tables and indexes are scanned so that the scans start at the end
2598
** and work toward the beginning rather than starting at the beginning and
2599
** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
2600
** same as setting [PRAGMA reverse_unordered_selects]. <p>This option takes
2601
** two arguments which are an integer and a pointer to an integer. The first
2602
** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
2603
** reverse scan order flag, respectively. If the second argument is not NULL,
2604
** then 0 or 1 is written into the integer that the second argument points to
2605
** depending on if the reverse scan order flag is set after processing the
2606
** first argument.
2607
** </dd>
2608
**
2609
** [[SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]]
2610
** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE</dt>
2611
** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE option enables or disables
2612
** the ability of the [ATTACH DATABASE] SQL command to create a new database
2613
** file if the database filed named in the ATTACH command does not already
2614
** exist. This ability of ATTACH to create a new database is enabled by
2615
** default. Applications can disable or reenable the ability for ATTACH to
2616
** create new database files using this DBCONFIG option.<p>
2617
** This option takes two arguments which are an integer and a pointer
2618
** to an integer. The first argument is 1, 0, or -1 to enable, disable, or
2619
** leave unchanged the attach-create flag, respectively. If the second
2620
** argument is not NULL, then 0 or 1 is written into the integer that the
2621
** second argument points to depending on if the attach-create flag is set
2622
** after processing the first argument.
2623
** </dd>
2624
**
2625
** [[SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE]]
2626
** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE</dt>
2627
** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE option enables or disables the
2628
** ability of the [ATTACH DATABASE] SQL command to open a database for writing.
2629
** This capability is enabled by default. Applications can disable or
2630
** reenable this capability using the current DBCONFIG option. If
2631
** this capability is disabled, the [ATTACH] command will still work,
2632
** but the database will be opened read-only. If this option is disabled,
2633
** then the ability to create a new database using [ATTACH] is also disabled,
2634
** regardless of the value of the [SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]
2635
** option.<p>
2636
** This option takes two arguments which are an integer and a pointer
2637
** to an integer. The first argument is 1, 0, or -1 to enable, disable, or
2638
** leave unchanged the ability to ATTACH another database for writing,
2639
** respectively. If the second argument is not NULL, then 0 or 1 is written
2640
** into the integer to which the second argument points, depending on whether
2641
** the ability to ATTACH a read/write database is enabled or disabled
2642
** after processing the first argument.
2643
** </dd>
2644
**
2645
** [[SQLITE_DBCONFIG_ENABLE_COMMENTS]]
2646
** <dt>SQLITE_DBCONFIG_ENABLE_COMMENTS</dt>
2647
** <dd>The SQLITE_DBCONFIG_ENABLE_COMMENTS option enables or disables the
2648
** ability to include comments in SQL text. Comments are enabled by default.
2649
** An application can disable or reenable comments in SQL text using this
2650
** DBCONFIG option.<p>
2651
** This option takes two arguments which are an integer and a pointer
2652
** to an integer. The first argument is 1, 0, or -1 to enable, disable, or
2653
** leave unchanged the ability to use comments in SQL text,
2654
** respectively. If the second argument is not NULL, then 0 or 1 is written
2655
** into the integer that the second argument points to depending on if
2656
** comments are allowed in SQL text after processing the first argument.
2657
** </dd>
2658
**
2659
** [[SQLITE_DBCONFIG_FP_DIGITS]]
2660
** <dt>SQLITE_DBCONFIG_FP_DIGITS</dt>
2661
** <dd>The SQLITE_DBCONFIG_FP_DIGITS setting is a small integer that determines
2662
** the number of significant digits that SQLite will attempt to preserve when
2663
** converting floating point numbers (IEEE 754 "doubles") into text. The
2664
** default value 17, as of SQLite version 3.52.0. The value was 15 in all
2665
** prior versions.<p>
2666
** This option takes two arguments which are an integer and a pointer
2667
** to an integer. The first argument is a small integer, between 3 and 23, or
2668
** zero. The FP_DIGITS setting is changed to that small integer, or left
2669
** unaltered if the first argument is zero or out of range. The second argument
2670
** is a pointer to an integer. If the pointer is not NULL, then the value of
2671
** the FP_DIGITS setting, after possibly being modified by the first
2672
** arguments, is written into the integer to which the second argument points.
2673
** </dd>
2674
**
2675
** </dl>
2676
**
2677
** [[DBCONFIG arguments]] <h3>Arguments To SQLITE_DBCONFIG Options</h3>
2678
**
2679
** <p>Most of the SQLITE_DBCONFIG options take two arguments, so that the
2680
** overall call to [sqlite3_db_config()] has a total of four parameters.
2681
** The first argument (the third parameter to sqlite3_db_config()) is
2682
** an integer.
2683
** The second argument is a pointer to an integer. If the first argument is 1,
2684
** then the option becomes enabled. If the first integer argument is 0,
2685
** then the option is disabled.
2686
** If the first argument is -1, then the option setting
2687
** is unchanged. The second argument, the pointer to an integer, may be NULL.
2688
** If the second argument is not NULL, then a value of 0 or 1 is written into
2689
** the integer to which the second argument points, depending on whether the
2690
** setting is disabled or enabled after applying any changes specified by
2691
** the first argument.
2692
**
2693
** <p>While most SQLITE_DBCONFIG options use the argument format
2694
** described in the previous paragraph, the [SQLITE_DBCONFIG_MAINDBNAME],
2695
** [SQLITE_DBCONFIG_LOOKASIDE], and [SQLITE_DBCONFIG_FP_DIGITS] options
2696
** are different. See the documentation of those exceptional options for
2697
** details.
2698
*/
2699
#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */
2700
#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
2701
#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
2702
#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
2703
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2704
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2705
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */
2706
#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */
2707
#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */
2708
#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */
2709
#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */
2710
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */
2711
#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */
2712
#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */
2713
#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */
2714
#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */
2715
#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */
2716
#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */
2717
#define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */
2718
#define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */
2719
#define SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE 1020 /* int int* */
2720
#define SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE 1021 /* int int* */
2721
#define SQLITE_DBCONFIG_ENABLE_COMMENTS 1022 /* int int* */
2722
#define SQLITE_DBCONFIG_FP_DIGITS 1023 /* int int* */
2723
#define SQLITE_DBCONFIG_MAX 1023 /* Largest DBCONFIG */
2724
2725
/*
2726
** CAPI3REF: Enable Or Disable Extended Result Codes
2727
** METHOD: sqlite3
2728
**
2729
** ^The sqlite3_extended_result_codes() routine enables or disables the
2730
** [extended result codes] feature of SQLite. ^The extended result
2731
** codes are disabled by default for historical compatibility.
2732
*/
2733
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2734
2735
/*
2736
** CAPI3REF: Last Insert Rowid
2737
** METHOD: sqlite3
2738
**
2739
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2740
** has a unique 64-bit signed
2741
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2742
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2743
** names are not also used by explicitly declared columns. ^If
2744
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2745
** is another alias for the rowid.
2746
**
2747
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2748
** the most recent successful [INSERT] into a rowid table or [virtual table]
2749
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2750
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2751
** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2752
** zero.
2753
**
2754
** As well as being set automatically as rows are inserted into database
2755
** tables, the value returned by this function may be set explicitly by
2756
** [sqlite3_set_last_insert_rowid()]
2757
**
2758
** Some virtual table implementations may INSERT rows into rowid tables as
2759
** part of committing a transaction (e.g. to flush data accumulated in memory
2760
** to disk). In this case subsequent calls to this function return the rowid
2761
** associated with these internal INSERT operations, which leads to
2762
** unintuitive results. Virtual table implementations that do write to rowid
2763
** tables in this way can avoid this problem by restoring the original
2764
** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2765
** control to the user.
2766
**
2767
** ^(If an [INSERT] occurs within a trigger then this routine will
2768
** return the [rowid] of the inserted row as long as the trigger is
2769
** running. Once the trigger program ends, the value returned
2770
** by this routine reverts to what it was before the trigger was fired.)^
2771
**
2772
** ^An [INSERT] that fails due to a constraint violation is not a
2773
** successful [INSERT] and does not change the value returned by this
2774
** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2775
** and INSERT OR ABORT make no changes to the return value of this
2776
** routine when their insertion fails. ^(When INSERT OR REPLACE
2777
** encounters a constraint violation, it does not fail. The
2778
** INSERT continues to completion after deleting rows that caused
2779
** the constraint problem so INSERT OR REPLACE will always change
2780
** the return value of this interface.)^
2781
**
2782
** ^For the purposes of this routine, an [INSERT] is considered to
2783
** be successful even if it is subsequently rolled back.
2784
**
2785
** This function is accessible to SQL statements via the
2786
** [last_insert_rowid() SQL function].
2787
**
2788
** If a separate thread performs a new [INSERT] on the same
2789
** database connection while the [sqlite3_last_insert_rowid()]
2790
** function is running and thus changes the last insert [rowid],
2791
** then the value returned by [sqlite3_last_insert_rowid()] is
2792
** unpredictable and might not equal either the old or the new
2793
** last insert [rowid].
2794
*/
2795
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2796
2797
/*
2798
** CAPI3REF: Set the Last Insert Rowid value.
2799
** METHOD: sqlite3
2800
**
2801
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2802
** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2803
** without inserting a row into the database.
2804
*/
2805
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2806
2807
/*
2808
** CAPI3REF: Count The Number Of Rows Modified
2809
** METHOD: sqlite3
2810
**
2811
** ^These functions return the number of rows modified, inserted or
2812
** deleted by the most recently completed INSERT, UPDATE or DELETE
2813
** statement on the database connection specified by the only parameter.
2814
** The two functions are identical except for the type of the return value
2815
** and that if the number of rows modified by the most recent INSERT, UPDATE,
2816
** or DELETE is greater than the maximum value supported by type "int", then
2817
** the return value of sqlite3_changes() is undefined. ^Executing any other
2818
** type of SQL statement does not modify the value returned by these functions.
2819
** For the purposes of this interface, a CREATE TABLE AS SELECT statement
2820
** does not count as an INSERT, UPDATE or DELETE statement and hence the rows
2821
** added to the new table by the CREATE TABLE AS SELECT statement are not
2822
** counted.
2823
**
2824
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2825
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2826
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2827
**
2828
** Changes to a view that are intercepted by
2829
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2830
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2831
** DELETE statement run on a view is always zero. Only changes made to real
2832
** tables are counted.
2833
**
2834
** Things are more complicated if the sqlite3_changes() function is
2835
** executed while a trigger program is running. This may happen if the
2836
** program uses the [changes() SQL function], or if some other callback
2837
** function invokes sqlite3_changes() directly. Essentially:
2838
**
2839
** <ul>
2840
** <li> ^(Before entering a trigger program the value returned by
2841
** sqlite3_changes() function is saved. After the trigger program
2842
** has finished, the original value is restored.)^
2843
**
2844
** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2845
** statement sets the value returned by sqlite3_changes()
2846
** upon completion as normal. Of course, this value will not include
2847
** any changes performed by sub-triggers, as the sqlite3_changes()
2848
** value will be saved and restored after each sub-trigger has run.)^
2849
** </ul>
2850
**
2851
** ^This means that if the changes() SQL function (or similar) is used
2852
** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2853
** returns the value as set when the calling statement began executing.
2854
** ^If it is used by the second or subsequent such statement within a trigger
2855
** program, the value returned reflects the number of rows modified by the
2856
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2857
**
2858
** If a separate thread makes changes on the same database connection
2859
** while [sqlite3_changes()] is running then the value returned
2860
** is unpredictable and not meaningful.
2861
**
2862
** See also:
2863
** <ul>
2864
** <li> the [sqlite3_total_changes()] interface
2865
** <li> the [count_changes pragma]
2866
** <li> the [changes() SQL function]
2867
** <li> the [data_version pragma]
2868
** </ul>
2869
*/
2870
SQLITE_API int sqlite3_changes(sqlite3*);
2871
SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2872
2873
/*
2874
** CAPI3REF: Total Number Of Rows Modified
2875
** METHOD: sqlite3
2876
**
2877
** ^These functions return the total number of rows inserted, modified or
2878
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2879
** since the database connection was opened, including those executed as
2880
** part of trigger programs. The two functions are identical except for the
2881
** type of the return value and that if the number of rows modified by the
2882
** connection exceeds the maximum value supported by type "int", then
2883
** the return value of sqlite3_total_changes() is undefined. ^Executing
2884
** any other type of SQL statement does not affect the value returned by
2885
** sqlite3_total_changes().
2886
**
2887
** ^Changes made as part of [foreign key actions] are included in the
2888
** count, but those made as part of REPLACE constraint resolution are
2889
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2890
** are not counted.
2891
**
2892
** The [sqlite3_total_changes(D)] interface only reports the number
2893
** of rows that changed due to SQL statement run against database
2894
** connection D. Any changes by other database connections are ignored.
2895
** To detect changes against a database file from other database
2896
** connections use the [PRAGMA data_version] command or the
2897
** [SQLITE_FCNTL_DATA_VERSION] [file control].
2898
**
2899
** If a separate thread makes changes on the same database connection
2900
** while [sqlite3_total_changes()] is running then the value
2901
** returned is unpredictable and not meaningful.
2902
**
2903
** See also:
2904
** <ul>
2905
** <li> the [sqlite3_changes()] interface
2906
** <li> the [count_changes pragma]
2907
** <li> the [changes() SQL function]
2908
** <li> the [data_version pragma]
2909
** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2910
** </ul>
2911
*/
2912
SQLITE_API int sqlite3_total_changes(sqlite3*);
2913
SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
2914
2915
/*
2916
** CAPI3REF: Interrupt A Long-Running Query
2917
** METHOD: sqlite3
2918
**
2919
** ^This function causes any pending database operation to abort and
2920
** return at its earliest opportunity. This routine is typically
2921
** called in response to a user action such as pressing "Cancel"
2922
** or Ctrl-C where the user wants a long query operation to halt
2923
** immediately.
2924
**
2925
** ^It is safe to call this routine from a thread different from the
2926
** thread that is currently running the database operation. But it
2927
** is not safe to call this routine with a [database connection] that
2928
** is closed or might close before sqlite3_interrupt() returns.
2929
**
2930
** ^If an SQL operation is very nearly finished at the time when
2931
** sqlite3_interrupt() is called, then it might not have an opportunity
2932
** to be interrupted and might continue to completion.
2933
**
2934
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2935
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2936
** that is inside an explicit transaction, then the entire transaction
2937
** will be rolled back automatically.
2938
**
2939
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2940
** SQL statements on [database connection] D complete. ^Any new SQL statements
2941
** that are started after the sqlite3_interrupt() call and before the
2942
** running statement count reaches zero are interrupted as if they had been
2943
** running prior to the sqlite3_interrupt() call. ^New SQL statements
2944
** that are started after the running statement count reaches zero are
2945
** not effected by the sqlite3_interrupt().
2946
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2947
** SQL statements is a no-op and has no effect on SQL statements
2948
** that are started after the sqlite3_interrupt() call returns.
2949
**
2950
** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
2951
** or not an interrupt is currently in effect for [database connection] D.
2952
** It returns 1 if an interrupt is currently in effect, or 0 otherwise.
2953
*/
2954
SQLITE_API void sqlite3_interrupt(sqlite3*);
2955
SQLITE_API int sqlite3_is_interrupted(sqlite3*);
2956
2957
/*
2958
** CAPI3REF: Determine If An SQL Statement Is Complete
2959
**
2960
** These routines are useful during command-line input to determine if the
2961
** currently entered text seems to form a complete SQL statement or
2962
** if additional input is needed before sending the text into
2963
** SQLite for parsing. ^These routines return 1 if the input string
2964
** appears to be a complete SQL statement. ^A statement is judged to be
2965
** complete if it ends with a semicolon token and is not a prefix of a
2966
** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
2967
** string literals or quoted identifier names or comments are not
2968
** independent tokens (they are part of the token in which they are
2969
** embedded) and thus do not count as a statement terminator. ^Whitespace
2970
** and comments that follow the final semicolon are ignored.
2971
**
2972
** ^These routines return 0 if the statement is incomplete. ^If a
2973
** memory allocation fails, then SQLITE_NOMEM is returned.
2974
**
2975
** ^These routines do not parse the SQL statements and thus
2976
** will not detect syntactically incorrect SQL.
2977
**
2978
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2979
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2980
** automatically by sqlite3_complete16(). If that initialization fails,
2981
** then the return value from sqlite3_complete16() will be non-zero
2982
** regardless of whether or not the input SQL is complete.)^
2983
**
2984
** The input to [sqlite3_complete()] must be a zero-terminated
2985
** UTF-8 string.
2986
**
2987
** The input to [sqlite3_complete16()] must be a zero-terminated
2988
** UTF-16 string in native byte order.
2989
*/
2990
SQLITE_API int sqlite3_complete(const char *sql);
2991
SQLITE_API int sqlite3_complete16(const void *sql);
2992
2993
/*
2994
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2995
** KEYWORDS: {busy-handler callback} {busy handler}
2996
** METHOD: sqlite3
2997
**
2998
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2999
** that might be invoked with argument P whenever
3000
** an attempt is made to access a database table associated with
3001
** [database connection] D when another thread
3002
** or process has the table locked.
3003
** The sqlite3_busy_handler() interface is used to implement
3004
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
3005
**
3006
** ^If the busy callback is NULL, then [SQLITE_BUSY]
3007
** is returned immediately upon encountering the lock. ^If the busy callback
3008
** is not NULL, then the callback might be invoked with two arguments.
3009
**
3010
** ^The first argument to the busy handler is a copy of the void* pointer which
3011
** is the third argument to sqlite3_busy_handler(). ^The second argument to
3012
** the busy handler callback is the number of times that the busy handler has
3013
** been invoked previously for the same locking event. ^If the
3014
** busy callback returns 0, then no additional attempts are made to
3015
** access the database and [SQLITE_BUSY] is returned
3016
** to the application.
3017
** ^If the callback returns non-zero, then another attempt
3018
** is made to access the database and the cycle repeats.
3019
**
3020
** The presence of a busy handler does not guarantee that it will be invoked
3021
** when there is lock contention. ^If SQLite determines that invoking the busy
3022
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
3023
** to the application instead of invoking the
3024
** busy handler.
3025
** Consider a scenario where one process is holding a read lock that
3026
** it is trying to promote to a reserved lock and
3027
** a second process is holding a reserved lock that it is trying
3028
** to promote to an exclusive lock. The first process cannot proceed
3029
** because it is blocked by the second and the second process cannot
3030
** proceed because it is blocked by the first. If both processes
3031
** invoke the busy handlers, neither will make any progress. Therefore,
3032
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
3033
** will induce the first process to release its read lock and allow
3034
** the second process to proceed.
3035
**
3036
** ^The default busy callback is NULL.
3037
**
3038
** ^(There can only be a single busy handler defined for each
3039
** [database connection]. Setting a new busy handler clears any
3040
** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
3041
** or evaluating [PRAGMA busy_timeout=N] will change the
3042
** busy handler and thus clear any previously set busy handler.
3043
**
3044
** The busy callback should not take any actions which modify the
3045
** database connection that invoked the busy handler. In other words,
3046
** the busy handler is not reentrant. Any such actions
3047
** result in undefined behavior.
3048
**
3049
** A busy handler must not close the database connection
3050
** or [prepared statement] that invoked the busy handler.
3051
*/
3052
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
3053
3054
/*
3055
** CAPI3REF: Set A Busy Timeout
3056
** METHOD: sqlite3
3057
**
3058
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
3059
** for a specified amount of time when a table is locked. ^The handler
3060
** will sleep multiple times until at least "ms" milliseconds of sleeping
3061
** have accumulated. ^After at least "ms" milliseconds of sleeping,
3062
** the handler returns 0 which causes [sqlite3_step()] to return
3063
** [SQLITE_BUSY].
3064
**
3065
** ^Calling this routine with an argument less than or equal to zero
3066
** turns off all busy handlers.
3067
**
3068
** ^(There can only be a single busy handler for a particular
3069
** [database connection] at any given moment. If another busy handler
3070
** was defined (using [sqlite3_busy_handler()]) prior to calling
3071
** this routine, that other busy handler is cleared.)^
3072
**
3073
** See also: [PRAGMA busy_timeout]
3074
*/
3075
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
3076
3077
/*
3078
** CAPI3REF: Set the Setlk Timeout
3079
** METHOD: sqlite3
3080
**
3081
** This routine is only useful in SQLITE_ENABLE_SETLK_TIMEOUT builds. If
3082
** the VFS supports blocking locks, it sets the timeout in ms used by
3083
** eligible locks taken on wal mode databases by the specified database
3084
** handle. In non-SQLITE_ENABLE_SETLK_TIMEOUT builds, or if the VFS does
3085
** not support blocking locks, this function is a no-op.
3086
**
3087
** Passing 0 to this function disables blocking locks altogether. Passing
3088
** -1 to this function requests that the VFS blocks for a long time -
3089
** indefinitely if possible. The results of passing any other negative value
3090
** are undefined.
3091
**
3092
** Internally, each SQLite database handle stores two timeout values - the
3093
** busy-timeout (used for rollback mode databases, or if the VFS does not
3094
** support blocking locks) and the setlk-timeout (used for blocking locks
3095
** on wal-mode databases). The sqlite3_busy_timeout() method sets both
3096
** values, this function sets only the setlk-timeout value. Therefore,
3097
** to configure separate busy-timeout and setlk-timeout values for a single
3098
** database handle, call sqlite3_busy_timeout() followed by this function.
3099
**
3100
** Whenever the number of connections to a wal mode database falls from
3101
** 1 to 0, the last connection takes an exclusive lock on the database,
3102
** then checkpoints and deletes the wal file. While it is doing this, any
3103
** new connection that tries to read from the database fails with an
3104
** SQLITE_BUSY error. Or, if the SQLITE_SETLK_BLOCK_ON_CONNECT flag is
3105
** passed to this API, the new connection blocks until the exclusive lock
3106
** has been released.
3107
*/
3108
SQLITE_API int sqlite3_setlk_timeout(sqlite3*, int ms, int flags);
3109
3110
/*
3111
** CAPI3REF: Flags for sqlite3_setlk_timeout()
3112
*/
3113
#define SQLITE_SETLK_BLOCK_ON_CONNECT 0x01
3114
3115
/*
3116
** CAPI3REF: Convenience Routines For Running Queries
3117
** METHOD: sqlite3
3118
**
3119
** This is a legacy interface that is preserved for backwards compatibility.
3120
** Use of this interface is not recommended.
3121
**
3122
** Definition: A <b>result table</b> is a memory data structure created by the
3123
** [sqlite3_get_table()] interface. A result table records the
3124
** complete query results from one or more queries.
3125
**
3126
** The table conceptually has a number of rows and columns. But
3127
** these numbers are not part of the result table itself. These
3128
** numbers are obtained separately. Let N be the number of rows
3129
** and M be the number of columns.
3130
**
3131
** A result table is an array of pointers to zero-terminated UTF-8 strings.
3132
** There are (N+1)*M elements in the array. The first M pointers point
3133
** to zero-terminated strings that contain the names of the columns.
3134
** The remaining entries all point to query results. NULL values result
3135
** in NULL pointers. All other values are in their UTF-8 zero-terminated
3136
** string representation as returned by [sqlite3_column_text()].
3137
**
3138
** A result table might consist of one or more memory allocations.
3139
** It is not safe to pass a result table directly to [sqlite3_free()].
3140
** A result table should be deallocated using [sqlite3_free_table()].
3141
**
3142
** ^(As an example of the result table format, suppose a query result
3143
** is as follows:
3144
**
3145
** <blockquote><pre>
3146
** Name | Age
3147
** -----------------------
3148
** Alice | 43
3149
** Bob | 28
3150
** Cindy | 21
3151
** </pre></blockquote>
3152
**
3153
** There are two columns (M==2) and three rows (N==3). Thus the
3154
** result table has 8 entries. Suppose the result table is stored
3155
** in an array named azResult. Then azResult holds this content:
3156
**
3157
** <blockquote><pre>
3158
** azResult&#91;0] = "Name";
3159
** azResult&#91;1] = "Age";
3160
** azResult&#91;2] = "Alice";
3161
** azResult&#91;3] = "43";
3162
** azResult&#91;4] = "Bob";
3163
** azResult&#91;5] = "28";
3164
** azResult&#91;6] = "Cindy";
3165
** azResult&#91;7] = "21";
3166
** </pre></blockquote>)^
3167
**
3168
** ^The sqlite3_get_table() function evaluates one or more
3169
** semicolon-separated SQL statements in the zero-terminated UTF-8
3170
** string of its 2nd parameter and returns a result table to the
3171
** pointer given in its 3rd parameter.
3172
**
3173
** After the application has finished with the result from sqlite3_get_table(),
3174
** it must pass the result table pointer to sqlite3_free_table() in order to
3175
** release the memory that was malloced. Because of the way the
3176
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
3177
** function must not try to call [sqlite3_free()] directly. Only
3178
** [sqlite3_free_table()] is able to release the memory properly and safely.
3179
**
3180
** The sqlite3_get_table() interface is implemented as a wrapper around
3181
** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
3182
** to any internal data structures of SQLite. It uses only the public
3183
** interface defined here. As a consequence, errors that occur in the
3184
** wrapper layer outside of the internal [sqlite3_exec()] call are not
3185
** reflected in subsequent calls to [sqlite3_errcode()] or
3186
** [sqlite3_errmsg()].
3187
*/
3188
SQLITE_API int sqlite3_get_table(
3189
sqlite3 *db, /* An open database */
3190
const char *zSql, /* SQL to be evaluated */
3191
char ***pazResult, /* Results of the query */
3192
int *pnRow, /* Number of result rows written here */
3193
int *pnColumn, /* Number of result columns written here */
3194
char **pzErrmsg /* Error msg written here */
3195
);
3196
SQLITE_API void sqlite3_free_table(char **result);
3197
3198
/*
3199
** CAPI3REF: Formatted String Printing Functions
3200
**
3201
** These routines are work-alikes of the "printf()" family of functions
3202
** from the standard C library.
3203
** These routines understand most of the common formatting options from
3204
** the standard library printf()
3205
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
3206
** See the [built-in printf()] documentation for details.
3207
**
3208
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
3209
** results into memory obtained from [sqlite3_malloc64()].
3210
** The strings returned by these two routines should be
3211
** released by [sqlite3_free()]. ^Both routines return a
3212
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
3213
** memory to hold the resulting string.
3214
**
3215
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
3216
** the standard C library. The result is written into the
3217
** buffer supplied as the second parameter whose size is given by
3218
** the first parameter. Note that the order of the
3219
** first two parameters is reversed from snprintf().)^ This is an
3220
** historical accident that cannot be fixed without breaking
3221
** backwards compatibility. ^(Note also that sqlite3_snprintf()
3222
** returns a pointer to its buffer instead of the number of
3223
** characters actually written into the buffer.)^ We admit that
3224
** the number of characters written would be a more useful return
3225
** value but we cannot change the implementation of sqlite3_snprintf()
3226
** now without breaking compatibility.
3227
**
3228
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
3229
** guarantees that the buffer is always zero-terminated. ^The first
3230
** parameter "n" is the total size of the buffer, including space for
3231
** the zero terminator. So the longest string that can be completely
3232
** written will be n-1 characters.
3233
**
3234
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
3235
**
3236
** See also: [built-in printf()], [printf() SQL function]
3237
*/
3238
SQLITE_API char *sqlite3_mprintf(const char*,...);
3239
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
3240
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
3241
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
3242
3243
/*
3244
** CAPI3REF: Memory Allocation Subsystem
3245
**
3246
** The SQLite core uses these three routines for all of its own
3247
** internal memory allocation needs. "Core" in the previous sentence
3248
** does not include operating-system specific [VFS] implementation. The
3249
** Windows VFS uses native malloc() and free() for some operations.
3250
**
3251
** ^The sqlite3_malloc() routine returns a pointer to a block
3252
** of memory at least N bytes in length, where N is the parameter.
3253
** ^If sqlite3_malloc() is unable to obtain sufficient free
3254
** memory, it returns a NULL pointer. ^If the parameter N to
3255
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
3256
** a NULL pointer.
3257
**
3258
** ^The sqlite3_malloc64(N) routine works just like
3259
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
3260
** of a signed 32-bit integer.
3261
**
3262
** ^Calling sqlite3_free() with a pointer previously returned
3263
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
3264
** that it might be reused. ^The sqlite3_free() routine is
3265
** a no-op if it is called with a NULL pointer. Passing a NULL pointer
3266
** to sqlite3_free() is harmless. After being freed, memory
3267
** should neither be read nor written. Even reading previously freed
3268
** memory might result in a segmentation fault or other severe error.
3269
** Memory corruption, a segmentation fault, or other severe error
3270
** might result if sqlite3_free() is called with a non-NULL pointer that
3271
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
3272
**
3273
** ^The sqlite3_realloc(X,N) interface attempts to resize a
3274
** prior memory allocation X to be at least N bytes.
3275
** ^If the X parameter to sqlite3_realloc(X,N)
3276
** is a NULL pointer then its behavior is identical to calling
3277
** sqlite3_malloc(N).
3278
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
3279
** negative then the behavior is exactly the same as calling
3280
** sqlite3_free(X).
3281
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
3282
** of at least N bytes in size or NULL if insufficient memory is available.
3283
** ^If M is the size of the prior allocation, then min(N,M) bytes of the
3284
** prior allocation are copied into the beginning of the buffer returned
3285
** by sqlite3_realloc(X,N) and the prior allocation is freed.
3286
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
3287
** prior allocation is not freed.
3288
**
3289
** ^The sqlite3_realloc64(X,N) interface works the same as
3290
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
3291
** of a 32-bit signed integer.
3292
**
3293
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
3294
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
3295
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
3296
** ^The value returned by sqlite3_msize(X) might be larger than the number
3297
** of bytes requested when X was allocated. ^If X is a NULL pointer then
3298
** sqlite3_msize(X) returns zero. If X points to something that is not
3299
** the beginning of memory allocation, or if it points to a formerly
3300
** valid memory allocation that has now been freed, then the behavior
3301
** of sqlite3_msize(X) is undefined and possibly harmful.
3302
**
3303
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
3304
** sqlite3_malloc64(), and sqlite3_realloc64()
3305
** is always aligned to at least an 8 byte boundary, or to a
3306
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
3307
** option is used.
3308
**
3309
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
3310
** must be either NULL or else pointers obtained from a prior
3311
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
3312
** not yet been released.
3313
**
3314
** The application must not read or write any part of
3315
** a block of memory after it has been released using
3316
** [sqlite3_free()] or [sqlite3_realloc()].
3317
*/
3318
SQLITE_API void *sqlite3_malloc(int);
3319
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
3320
SQLITE_API void *sqlite3_realloc(void*, int);
3321
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
3322
SQLITE_API void sqlite3_free(void*);
3323
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
3324
3325
/*
3326
** CAPI3REF: Memory Allocator Statistics
3327
**
3328
** SQLite provides these two interfaces for reporting on the status
3329
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
3330
** routines, which form the built-in memory allocation subsystem.
3331
**
3332
** ^The [sqlite3_memory_used()] routine returns the number of bytes
3333
** of memory currently outstanding (malloced but not freed).
3334
** ^The [sqlite3_memory_highwater()] routine returns the maximum
3335
** value of [sqlite3_memory_used()] since the high-water mark
3336
** was last reset. ^The values returned by [sqlite3_memory_used()] and
3337
** [sqlite3_memory_highwater()] include any overhead
3338
** added by SQLite in its implementation of [sqlite3_malloc()],
3339
** but not overhead added by any underlying system library
3340
** routines that [sqlite3_malloc()] may call.
3341
**
3342
** ^The memory high-water mark is reset to the current value of
3343
** [sqlite3_memory_used()] if and only if the parameter to
3344
** [sqlite3_memory_highwater()] is true. ^The value returned
3345
** by [sqlite3_memory_highwater(1)] is the high-water mark
3346
** prior to the reset.
3347
*/
3348
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
3349
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
3350
3351
/*
3352
** CAPI3REF: Pseudo-Random Number Generator
3353
**
3354
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3355
** select random [ROWID | ROWIDs] when inserting new records into a table that
3356
** already uses the largest possible [ROWID]. The PRNG is also used for
3357
** the built-in random() and randomblob() SQL functions. This interface allows
3358
** applications to access the same PRNG for other purposes.
3359
**
3360
** ^A call to this routine stores N bytes of randomness into buffer P.
3361
** ^The P parameter can be a NULL pointer.
3362
**
3363
** ^If this routine has not been previously called or if the previous
3364
** call had N less than one or a NULL pointer for P, then the PRNG is
3365
** seeded using randomness obtained from the xRandomness method of
3366
** the default [sqlite3_vfs] object.
3367
** ^If the previous call to this routine had an N of 1 or more and a
3368
** non-NULL P then the pseudo-randomness is generated
3369
** internally and without recourse to the [sqlite3_vfs] xRandomness
3370
** method.
3371
*/
3372
SQLITE_API void sqlite3_randomness(int N, void *P);
3373
3374
/*
3375
** CAPI3REF: Compile-Time Authorization Callbacks
3376
** METHOD: sqlite3
3377
** KEYWORDS: {authorizer callback}
3378
**
3379
** ^This routine registers an authorizer callback with a particular
3380
** [database connection], supplied in the first argument.
3381
** ^The authorizer callback is invoked as SQL statements are being compiled
3382
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3383
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3384
** and [sqlite3_prepare16_v3()]. ^At various
3385
** points during the compilation process, as logic is being created
3386
** to perform various actions, the authorizer callback is invoked to
3387
** see if those actions are allowed. ^The authorizer callback should
3388
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3389
** specific action but allow the SQL statement to continue to be
3390
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3391
** rejected with an error. ^If the authorizer callback returns
3392
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3393
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3394
** the authorizer will fail with an error message.
3395
**
3396
** When the callback returns [SQLITE_OK], that means the operation
3397
** requested is ok. ^When the callback returns [SQLITE_DENY], the
3398
** [sqlite3_prepare_v2()] or equivalent call that triggered the
3399
** authorizer will fail with an error message explaining that
3400
** access is denied.
3401
**
3402
** ^The first parameter to the authorizer callback is a copy of the third
3403
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3404
** to the callback is an integer [SQLITE_COPY | action code] that specifies
3405
** the particular action to be authorized. ^The third through sixth parameters
3406
** to the callback are either NULL pointers or zero-terminated strings
3407
** that contain additional details about the action to be authorized.
3408
** Applications must always be prepared to encounter a NULL pointer in any
3409
** of the third through the sixth parameters of the authorization callback.
3410
**
3411
** ^If the action code is [SQLITE_READ]
3412
** and the callback returns [SQLITE_IGNORE] then the
3413
** [prepared statement] statement is constructed to substitute
3414
** a NULL value in place of the table column that would have
3415
** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
3416
** return can be used to deny an untrusted user access to individual
3417
** columns of a table.
3418
** ^When a table is referenced by a [SELECT] but no column values are
3419
** extracted from that table (for example in a query like
3420
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3421
** is invoked once for that table with a column name that is an empty string.
3422
** ^If the action code is [SQLITE_DELETE] and the callback returns
3423
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3424
** [truncate optimization] is disabled and all rows are deleted individually.
3425
**
3426
** An authorizer is used when [sqlite3_prepare | preparing]
3427
** SQL statements from an untrusted source, to ensure that the SQL statements
3428
** do not try to access data they are not allowed to see, or that they do not
3429
** try to execute malicious statements that damage the database. For
3430
** example, an application may allow a user to enter arbitrary
3431
** SQL queries for evaluation by a database. But the application does
3432
** not want the user to be able to make arbitrary changes to the
3433
** database. An authorizer could then be put in place while the
3434
** user-entered SQL is being [sqlite3_prepare | prepared] that
3435
** disallows everything except [SELECT] statements.
3436
**
3437
** Applications that need to process SQL from untrusted sources
3438
** might also consider lowering resource limits using [sqlite3_limit()]
3439
** and limiting database size using the [max_page_count] [PRAGMA]
3440
** in addition to using an authorizer.
3441
**
3442
** ^(Only a single authorizer can be in place on a database connection
3443
** at a time. Each call to sqlite3_set_authorizer overrides the
3444
** previous call.)^ ^Disable the authorizer by installing a NULL callback.
3445
** The authorizer is disabled by default.
3446
**
3447
** The authorizer callback must not do anything that will modify
3448
** the database connection that invoked the authorizer callback.
3449
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3450
** database connections for the meaning of "modify" in this paragraph.
3451
**
3452
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3453
** statement might be re-prepared during [sqlite3_step()] due to a
3454
** schema change. Hence, the application should ensure that the
3455
** correct authorizer callback remains in place during the [sqlite3_step()].
3456
**
3457
** ^Note that the authorizer callback is invoked only during
3458
** [sqlite3_prepare()] or its variants. Authorization is not
3459
** performed during statement evaluation in [sqlite3_step()], unless
3460
** as stated in the previous paragraph, sqlite3_step() invokes
3461
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3462
*/
3463
SQLITE_API int sqlite3_set_authorizer(
3464
sqlite3*,
3465
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3466
void *pUserData
3467
);
3468
3469
/*
3470
** CAPI3REF: Authorizer Return Codes
3471
**
3472
** The [sqlite3_set_authorizer | authorizer callback function] must
3473
** return either [SQLITE_OK] or one of these two constants in order
3474
** to signal SQLite whether or not the action is permitted. See the
3475
** [sqlite3_set_authorizer | authorizer documentation] for additional
3476
** information.
3477
**
3478
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3479
** returned from the [sqlite3_vtab_on_conflict()] interface.
3480
*/
3481
#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
3482
#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
3483
3484
/*
3485
** CAPI3REF: Authorizer Action Codes
3486
**
3487
** The [sqlite3_set_authorizer()] interface registers a callback function
3488
** that is invoked to authorize certain SQL statement actions. The
3489
** second parameter to the callback is an integer code that specifies
3490
** what action is being authorized. These are the integer action codes that
3491
** the authorizer callback may be passed.
3492
**
3493
** These action code values signify what kind of operation is to be
3494
** authorized. The 3rd and 4th parameters to the authorization
3495
** callback function will be parameters or NULL depending on which of these
3496
** codes is used as the second parameter. ^(The 5th parameter to the
3497
** authorizer callback is the name of the database ("main", "temp",
3498
** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
3499
** is the name of the inner-most trigger or view that is responsible for
3500
** the access attempt or NULL if this access attempt is directly from
3501
** top-level SQL code.
3502
*/
3503
/******************************************* 3rd ************ 4th ***********/
3504
#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
3505
#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
3506
#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
3507
#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
3508
#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
3509
#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
3510
#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
3511
#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
3512
#define SQLITE_DELETE 9 /* Table Name NULL */
3513
#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
3514
#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
3515
#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
3516
#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
3517
#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
3518
#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
3519
#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
3520
#define SQLITE_DROP_VIEW 17 /* View Name NULL */
3521
#define SQLITE_INSERT 18 /* Table Name NULL */
3522
#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
3523
#define SQLITE_READ 20 /* Table Name Column Name */
3524
#define SQLITE_SELECT 21 /* NULL NULL */
3525
#define SQLITE_TRANSACTION 22 /* Operation NULL */
3526
#define SQLITE_UPDATE 23 /* Table Name Column Name */
3527
#define SQLITE_ATTACH 24 /* Filename NULL */
3528
#define SQLITE_DETACH 25 /* Database Name NULL */
3529
#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
3530
#define SQLITE_REINDEX 27 /* Index Name NULL */
3531
#define SQLITE_ANALYZE 28 /* Table Name NULL */
3532
#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
3533
#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
3534
#define SQLITE_FUNCTION 31 /* NULL Function Name */
3535
#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
3536
#define SQLITE_COPY 0 /* No longer used */
3537
#define SQLITE_RECURSIVE 33 /* NULL NULL */
3538
3539
/*
3540
** CAPI3REF: Deprecated Tracing And Profiling Functions
3541
** DEPRECATED
3542
**
3543
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3544
** instead of the routines described here.
3545
**
3546
** These routines register callback functions that can be used for
3547
** tracing and profiling the execution of SQL statements.
3548
**
3549
** ^The callback function registered by sqlite3_trace() is invoked at
3550
** various times when an SQL statement is being run by [sqlite3_step()].
3551
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3552
** SQL statement text as the statement first begins executing.
3553
** ^(Additional sqlite3_trace() callbacks might occur
3554
** as each triggered subprogram is entered. The callbacks for triggers
3555
** contain a UTF-8 SQL comment that identifies the trigger.)^
3556
**
3557
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3558
** the length of [bound parameter] expansion in the output of sqlite3_trace().
3559
**
3560
** ^The callback function registered by sqlite3_profile() is invoked
3561
** as each SQL statement finishes. ^The profile callback contains
3562
** the original statement text and an estimate of wall-clock time
3563
** of how long that statement took to run. ^The profile callback
3564
** time is in units of nanoseconds, however the current implementation
3565
** is only capable of millisecond resolution so the six least significant
3566
** digits in the time are meaningless. Future versions of SQLite
3567
** might provide greater resolution on the profiler callback. Invoking
3568
** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3569
** profile callback.
3570
*/
3571
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3572
void(*xTrace)(void*,const char*), void*);
3573
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3574
void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3575
3576
/*
3577
** CAPI3REF: SQL Trace Event Codes
3578
** KEYWORDS: SQLITE_TRACE
3579
**
3580
** These constants identify classes of events that can be monitored
3581
** using the [sqlite3_trace_v2()] tracing logic. The M argument
3582
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3583
** the following constants. ^The first argument to the trace callback
3584
** is one of the following constants.
3585
**
3586
** New tracing constants may be added in future releases.
3587
**
3588
** ^A trace callback has four arguments: xCallback(T,C,P,X).
3589
** ^The T argument is one of the integer type codes above.
3590
** ^The C argument is a copy of the context pointer passed in as the
3591
** fourth argument to [sqlite3_trace_v2()].
3592
** The P and X arguments are pointers whose meanings depend on T.
3593
**
3594
** <dl>
3595
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3596
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3597
** first begins running and possibly at other times during the
3598
** execution of the prepared statement, such as at the start of each
3599
** trigger subprogram. ^The P argument is a pointer to the
3600
** [prepared statement]. ^The X argument is a pointer to a string which
3601
** is the unexpanded SQL text of the prepared statement or an SQL comment
3602
** that indicates the invocation of a trigger. ^The callback can compute
3603
** the same text that would have been returned by the legacy [sqlite3_trace()]
3604
** interface by using the X argument when X begins with "--" and invoking
3605
** [sqlite3_expanded_sql(P)] otherwise.
3606
**
3607
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3608
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3609
** information as is provided by the [sqlite3_profile()] callback.
3610
** ^The P argument is a pointer to the [prepared statement] and the
3611
** X argument points to a 64-bit integer which is approximately
3612
** the number of nanoseconds that the prepared statement took to run.
3613
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3614
**
3615
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3616
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3617
** statement generates a single row of result.
3618
** ^The P argument is a pointer to the [prepared statement] and the
3619
** X argument is unused.
3620
**
3621
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3622
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3623
** connection closes.
3624
** ^The P argument is a pointer to the [database connection] object
3625
** and the X argument is unused.
3626
** </dl>
3627
*/
3628
#define SQLITE_TRACE_STMT 0x01
3629
#define SQLITE_TRACE_PROFILE 0x02
3630
#define SQLITE_TRACE_ROW 0x04
3631
#define SQLITE_TRACE_CLOSE 0x08
3632
3633
/*
3634
** CAPI3REF: SQL Trace Hook
3635
** METHOD: sqlite3
3636
**
3637
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3638
** function X against [database connection] D, using property mask M
3639
** and context pointer P. ^If the X callback is
3640
** NULL or if the M mask is zero, then tracing is disabled. The
3641
** M argument should be the bitwise OR-ed combination of
3642
** zero or more [SQLITE_TRACE] constants.
3643
**
3644
** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P)
3645
** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or
3646
** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each
3647
** database connection may have at most one trace callback.
3648
**
3649
** ^The X callback is invoked whenever any of the events identified by
3650
** mask M occur. ^The integer return value from the callback is currently
3651
** ignored, though this may change in future releases. Callback
3652
** implementations should return zero to ensure future compatibility.
3653
**
3654
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3655
** ^The T argument is one of the [SQLITE_TRACE]
3656
** constants to indicate why the callback was invoked.
3657
** ^The C argument is a copy of the context pointer.
3658
** The P and X arguments are pointers whose meanings depend on T.
3659
**
3660
** The sqlite3_trace_v2() interface is intended to replace the legacy
3661
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3662
** are deprecated.
3663
*/
3664
SQLITE_API int sqlite3_trace_v2(
3665
sqlite3*,
3666
unsigned uMask,
3667
int(*xCallback)(unsigned,void*,void*,void*),
3668
void *pCtx
3669
);
3670
3671
/*
3672
** CAPI3REF: Query Progress Callbacks
3673
** METHOD: sqlite3
3674
**
3675
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3676
** function X to be invoked periodically during long running calls to
3677
** [sqlite3_step()] and [sqlite3_prepare()] and similar for
3678
** database connection D. An example use for this
3679
** interface is to keep a GUI updated during a large query.
3680
**
3681
** ^The parameter P is passed through as the only parameter to the
3682
** callback function X. ^The parameter N is the approximate number of
3683
** [virtual machine instructions] that are evaluated between successive
3684
** invocations of the callback X. ^If N is less than one then the progress
3685
** handler is disabled.
3686
**
3687
** ^Only a single progress handler may be defined at one time per
3688
** [database connection]; setting a new progress handler cancels the
3689
** old one. ^Setting parameter X to NULL disables the progress handler.
3690
** ^The progress handler is also disabled by setting N to a value less
3691
** than 1.
3692
**
3693
** ^If the progress callback returns non-zero, the operation is
3694
** interrupted. This feature can be used to implement a
3695
** "Cancel" button on a GUI progress dialog box.
3696
**
3697
** The progress handler callback must not do anything that will modify
3698
** the database connection that invoked the progress handler.
3699
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3700
** database connections for the meaning of "modify" in this paragraph.
3701
**
3702
** The progress handler callback would originally only be invoked from the
3703
** bytecode engine. It still might be invoked during [sqlite3_prepare()]
3704
** and similar because those routines might force a reparse of the schema
3705
** which involves running the bytecode engine. However, beginning with
3706
** SQLite version 3.41.0, the progress handler callback might also be
3707
** invoked directly from [sqlite3_prepare()] while analyzing and generating
3708
** code for complex queries.
3709
*/
3710
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3711
3712
/*
3713
** CAPI3REF: Opening A New Database Connection
3714
** CONSTRUCTOR: sqlite3
3715
**
3716
** ^These routines open an SQLite database file as specified by the
3717
** filename argument. ^The filename argument is interpreted as UTF-8 for
3718
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3719
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3720
** returned in *ppDb, even if an error occurs. The only exception is that
3721
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3722
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3723
** object.)^ ^(If the database is opened (and/or created) successfully, then
3724
** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
3725
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3726
** an English language description of the error following a failure of any
3727
** of the sqlite3_open() routines.
3728
**
3729
** ^The default encoding will be UTF-8 for databases created using
3730
** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases
3731
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3732
**
3733
** Whether or not an error occurs when it is opened, resources
3734
** associated with the [database connection] handle should be released by
3735
** passing it to [sqlite3_close()] when it is no longer required.
3736
**
3737
** The sqlite3_open_v2() interface works like sqlite3_open()
3738
** except that it accepts two additional parameters for additional control
3739
** over the new database connection. ^(The flags parameter to
3740
** sqlite3_open_v2() must include, at a minimum, one of the following
3741
** three flag combinations:)^
3742
**
3743
** <dl>
3744
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3745
** <dd>The database is opened in read-only mode. If the database does
3746
** not already exist, an error is returned.</dd>)^
3747
**
3748
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3749
** <dd>The database is opened for reading and writing if possible, or
3750
** reading only if the file is write protected by the operating
3751
** system. In either case the database must already exist, otherwise
3752
** an error is returned. For historical reasons, if opening in
3753
** read-write mode fails due to OS-level permissions, an attempt is
3754
** made to open it in read-only mode. [sqlite3_db_readonly()] can be
3755
** used to determine whether the database is actually
3756
** read-write.</dd>)^
3757
**
3758
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3759
** <dd>The database is opened for reading and writing, and is created if
3760
** it does not already exist. This is the behavior that is always used for
3761
** sqlite3_open() and sqlite3_open16().</dd>)^
3762
** </dl>
3763
**
3764
** In addition to the required flags, the following optional flags are
3765
** also supported:
3766
**
3767
** <dl>
3768
** ^(<dt>[SQLITE_OPEN_URI]</dt>
3769
** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3770
**
3771
** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3772
** <dd>The database will be opened as an in-memory database. The database
3773
** is named by the "filename" argument for the purposes of cache-sharing,
3774
** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3775
** </dd>)^
3776
**
3777
** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3778
** <dd>The new database connection will use the "multi-thread"
3779
** [threading mode].)^ This means that separate threads are allowed
3780
** to use SQLite at the same time, as long as each thread is using
3781
** a different [database connection].
3782
**
3783
** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3784
** <dd>The new database connection will use the "serialized"
3785
** [threading mode].)^ This means the multiple threads can safely
3786
** attempt to use the same database connection at the same time.
3787
** (Mutexes will block any actual concurrency, but in this mode
3788
** there is no harm in trying.)
3789
**
3790
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3791
** <dd>The database is opened with [shared cache] enabled, overriding
3792
** the default shared cache setting provided by
3793
** [sqlite3_enable_shared_cache()].)^
3794
** The [use of shared cache mode is discouraged] and hence shared cache
3795
** capabilities may be omitted from many builds of SQLite. In such cases,
3796
** this option is a no-op.
3797
**
3798
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3799
** <dd>The database is opened with [shared cache] disabled, overriding
3800
** the default shared cache setting provided by
3801
** [sqlite3_enable_shared_cache()].)^
3802
**
3803
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3804
** <dd>The database connection comes up in "extended result code mode".
3805
** In other words, the database behaves as if
3806
** [sqlite3_extended_result_codes(db,1)] were called on the database
3807
** connection as soon as the connection is created. In addition to setting
3808
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3809
** to return an extended result code.</dd>
3810
**
3811
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3812
** <dd>The database filename is not allowed to contain a symbolic link</dd>
3813
** </dl>)^
3814
**
3815
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3816
** required combinations shown above optionally combined with other
3817
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3818
** then the behavior is undefined. Historic versions of SQLite
3819
** have silently ignored surplus bits in the flags parameter to
3820
** sqlite3_open_v2(), however that behavior might not be carried through
3821
** into future versions of SQLite and so applications should not rely
3822
** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3823
** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause
3824
** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE
3825
** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3826
** by sqlite3_open_v2().
3827
**
3828
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3829
** [sqlite3_vfs] object that defines the operating system interface that
3830
** the new database connection should use. ^If the fourth parameter is
3831
** a NULL pointer then the default [sqlite3_vfs] object is used.
3832
**
3833
** ^If the filename is ":memory:", then a private, temporary in-memory database
3834
** is created for the connection. ^This in-memory database will vanish when
3835
** the database connection is closed. Future versions of SQLite might
3836
** make use of additional special filenames that begin with the ":" character.
3837
** It is recommended that when a database filename actually does begin with
3838
** a ":" character you should prefix the filename with a pathname such as
3839
** "./" to avoid ambiguity.
3840
**
3841
** ^If the filename is an empty string, then a private, temporary
3842
** on-disk database will be created. ^This private database will be
3843
** automatically deleted as soon as the database connection is closed.
3844
**
3845
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3846
**
3847
** ^If [URI filename] interpretation is enabled, and the filename argument
3848
** begins with "file:", then the filename is interpreted as a URI. ^URI
3849
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3850
** set in the third argument to sqlite3_open_v2(), or if it has
3851
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3852
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3853
** URI filename interpretation is turned off
3854
** by default, but future releases of SQLite might enable URI filename
3855
** interpretation by default. See "[URI filenames]" for additional
3856
** information.
3857
**
3858
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3859
** authority, then it must be either an empty string or the string
3860
** "localhost". ^If the authority is not an empty string or "localhost", an
3861
** error is returned to the caller. ^The fragment component of a URI, if
3862
** present, is ignored.
3863
**
3864
** ^SQLite uses the path component of the URI as the name of the disk file
3865
** which contains the database. ^If the path begins with a '/' character,
3866
** then it is interpreted as an absolute path. ^If the path does not begin
3867
** with a '/' (meaning that the authority section is omitted from the URI)
3868
** then the path is interpreted as a relative path.
3869
** ^(On windows, the first component of an absolute path
3870
** is a drive specification (e.g. "C:").)^
3871
**
3872
** [[core URI query parameters]]
3873
** The query component of a URI may contain parameters that are interpreted
3874
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3875
** SQLite and its built-in [VFSes] interpret the
3876
** following query parameters:
3877
**
3878
** <ul>
3879
** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3880
** a VFS object that provides the operating system interface that should
3881
** be used to access the database file on disk. ^If this option is set to
3882
** an empty string the default VFS object is used. ^Specifying an unknown
3883
** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3884
** present, then the VFS specified by the option takes precedence over
3885
** the value passed as the fourth parameter to sqlite3_open_v2().
3886
**
3887
** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3888
** "rwc", or "memory". Attempting to set it to any other value is
3889
** an error)^.
3890
** ^If "ro" is specified, then the database is opened for read-only
3891
** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3892
** third argument to sqlite3_open_v2(). ^If the mode option is set to
3893
** "rw", then the database is opened for read-write (but not create)
3894
** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3895
** been set. ^Value "rwc" is equivalent to setting both
3896
** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is
3897
** set to "memory" then a pure [in-memory database] that never reads
3898
** or writes from disk is used. ^It is an error to specify a value for
3899
** the mode parameter that is less restrictive than that specified by
3900
** the flags passed in the third parameter to sqlite3_open_v2().
3901
**
3902
** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3903
** "private". ^Setting it to "shared" is equivalent to setting the
3904
** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3905
** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3906
** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3907
** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3908
** a URI filename, its value overrides any behavior requested by setting
3909
** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3910
**
3911
** <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3912
** [powersafe overwrite] property does or does not apply to the
3913
** storage media on which the database file resides.
3914
**
3915
** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3916
** which if set disables file locking in rollback journal modes. This
3917
** is useful for accessing a database on a filesystem that does not
3918
** support locking. Caution: Database corruption might result if two
3919
** or more processes write to the same database and any one of those
3920
** processes uses nolock=1.
3921
**
3922
** <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3923
** parameter that indicates that the database file is stored on
3924
** read-only media. ^When immutable is set, SQLite assumes that the
3925
** database file cannot be changed, even by a process with higher
3926
** privilege, and so the database is opened read-only and all locking
3927
** and change detection is disabled. Caution: Setting the immutable
3928
** property on a database file that does in fact change can result
3929
** in incorrect query results and/or [SQLITE_CORRUPT] errors.
3930
** See also: [SQLITE_IOCAP_IMMUTABLE].
3931
**
3932
** </ul>
3933
**
3934
** ^Specifying an unknown parameter in the query component of a URI is not an
3935
** error. Future versions of SQLite might understand additional query
3936
** parameters. See "[query parameters with special meaning to SQLite]" for
3937
** additional information.
3938
**
3939
** [[URI filename examples]] <h3>URI filename examples</h3>
3940
**
3941
** <table border="1" align=center cellpadding=5>
3942
** <tr><th> URI filenames <th> Results
3943
** <tr><td> file:data.db <td>
3944
** Open the file "data.db" in the current directory.
3945
** <tr><td> file:/home/fred/data.db<br>
3946
** file:///home/fred/data.db <br>
3947
** file://localhost/home/fred/data.db <br> <td>
3948
** Open the database file "/home/fred/data.db".
3949
** <tr><td> file://darkstar/home/fred/data.db <td>
3950
** An error. "darkstar" is not a recognized authority.
3951
** <tr><td style="white-space:nowrap">
3952
** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3953
** <td> Windows only: Open the file "data.db" on fred's desktop on drive
3954
** C:. Note that the %20 escaping in this example is not strictly
3955
** necessary - space characters can be used literally
3956
** in URI filenames.
3957
** <tr><td> file:data.db?mode=ro&cache=private <td>
3958
** Open file "data.db" in the current directory for read-only access.
3959
** Regardless of whether or not shared-cache mode is enabled by
3960
** default, use a private cache.
3961
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3962
** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3963
** that uses dot-files in place of posix advisory locking.
3964
** <tr><td> file:data.db?mode=readonly <td>
3965
** An error. "readonly" is not a valid option for the "mode" parameter.
3966
** Use "ro" instead: "file:data.db?mode=ro".
3967
** </table>
3968
**
3969
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3970
** query components of a URI. A hexadecimal escape sequence consists of a
3971
** percent sign - "%" - followed by exactly two hexadecimal digits
3972
** specifying an octet value. ^Before the path or query components of a
3973
** URI filename are interpreted, they are encoded using UTF-8 and all
3974
** hexadecimal escape sequences replaced by a single byte containing the
3975
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3976
** the results are undefined.
3977
**
3978
** <b>Note to Windows users:</b> The encoding used for the filename argument
3979
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3980
** codepage is currently defined. Filenames containing international
3981
** characters must be converted to UTF-8 prior to passing them into
3982
** sqlite3_open() or sqlite3_open_v2().
3983
**
3984
** <b>Note to Windows Runtime users:</b> The temporary directory must be set
3985
** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various
3986
** features that require the use of temporary files may fail.
3987
**
3988
** See also: [sqlite3_temp_directory]
3989
*/
3990
SQLITE_API int sqlite3_open(
3991
const char *filename, /* Database filename (UTF-8) */
3992
sqlite3 **ppDb /* OUT: SQLite db handle */
3993
);
3994
SQLITE_API int sqlite3_open16(
3995
const void *filename, /* Database filename (UTF-16) */
3996
sqlite3 **ppDb /* OUT: SQLite db handle */
3997
);
3998
SQLITE_API int sqlite3_open_v2(
3999
const char *filename, /* Database filename (UTF-8) */
4000
sqlite3 **ppDb, /* OUT: SQLite db handle */
4001
int flags, /* Flags */
4002
const char *zVfs /* Name of VFS module to use */
4003
);
4004
4005
/*
4006
** CAPI3REF: Obtain Values For URI Parameters
4007
**
4008
** These are utility routines, useful to [VFS|custom VFS implementations],
4009
** that check if a database file was a URI that contained a specific query
4010
** parameter, and if so obtains the value of that query parameter.
4011
**
4012
** The first parameter to these interfaces (hereafter referred to
4013
** as F) must be one of:
4014
** <ul>
4015
** <li> A database filename pointer created by the SQLite core and
4016
** passed into the xOpen() method of a VFS implementation, or
4017
** <li> A filename obtained from [sqlite3_db_filename()], or
4018
** <li> A new filename constructed using [sqlite3_create_filename()].
4019
** </ul>
4020
** If the F parameter is not one of the above, then the behavior is
4021
** undefined and probably undesirable. Older versions of SQLite were
4022
** more tolerant of invalid F parameters than newer versions.
4023
**
4024
** If F is a suitable filename (as described in the previous paragraph)
4025
** and if P is the name of the query parameter, then
4026
** sqlite3_uri_parameter(F,P) returns the value of the P
4027
** parameter if it exists or a NULL pointer if P does not appear as a
4028
** query parameter on F. If P is a query parameter of F and it
4029
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
4030
** a pointer to an empty string.
4031
**
4032
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
4033
** parameter and returns true (1) or false (0) according to the value
4034
** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
4035
** value of query parameter P is one of "yes", "true", or "on" in any
4036
** case or if the value begins with a non-zero number. The
4037
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
4038
** query parameter P is one of "no", "false", or "off" in any case or
4039
** if the value begins with a numeric zero. If P is not a query
4040
** parameter on F or if the value of P does not match any of the
4041
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
4042
**
4043
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
4044
** 64-bit signed integer and returns that integer, or D if P does not
4045
** exist. If the value of P is something other than an integer, then
4046
** zero is returned.
4047
**
4048
** The sqlite3_uri_key(F,N) returns a pointer to the name (not
4049
** the value) of the N-th query parameter for filename F, or a NULL
4050
** pointer if N is less than zero or greater than the number of query
4051
** parameters minus 1. The N value is zero-based so N should be 0 to obtain
4052
** the name of the first query parameter, 1 for the second parameter, and
4053
** so forth.
4054
**
4055
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
4056
** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
4057
** is not a database file pathname pointer that the SQLite core passed
4058
** into the xOpen VFS method, then the behavior of this routine is undefined
4059
** and probably undesirable.
4060
**
4061
** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
4062
** parameter can also be the name of a rollback journal file or WAL file
4063
** in addition to the main database file. Prior to version 3.31.0, these
4064
** routines would only work if F was the name of the main database file.
4065
** When the F parameter is the name of the rollback journal or WAL file,
4066
** it has access to all the same query parameters as were found on the
4067
** main database file.
4068
**
4069
** See the [URI filename] documentation for additional information.
4070
*/
4071
SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
4072
SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
4073
SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
4074
SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);
4075
4076
/*
4077
** CAPI3REF: Translate filenames
4078
**
4079
** These routines are available to [VFS|custom VFS implementations] for
4080
** translating filenames between the main database file, the journal file,
4081
** and the WAL file.
4082
**
4083
** If F is the name of an sqlite database file, journal file, or WAL file
4084
** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
4085
** returns the name of the corresponding database file.
4086
**
4087
** If F is the name of an sqlite database file, journal file, or WAL file
4088
** passed by the SQLite core into the VFS, or if F is a database filename
4089
** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
4090
** returns the name of the corresponding rollback journal file.
4091
**
4092
** If F is the name of an sqlite database file, journal file, or WAL file
4093
** that was passed by the SQLite core into the VFS, or if F is a database
4094
** filename obtained from [sqlite3_db_filename()], then
4095
** sqlite3_filename_wal(F) returns the name of the corresponding
4096
** WAL file.
4097
**
4098
** In all of the above, if F is not the name of a database, journal or WAL
4099
** filename passed into the VFS from the SQLite core and F is not the
4100
** return value from [sqlite3_db_filename()], then the result is
4101
** undefined and is likely a memory access violation.
4102
*/
4103
SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
4104
SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
4105
SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);
4106
4107
/*
4108
** CAPI3REF: Database File Corresponding To A Journal
4109
**
4110
** ^If X is the name of a rollback or WAL-mode journal file that is
4111
** passed into the xOpen method of [sqlite3_vfs], then
4112
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
4113
** object that represents the main database file.
4114
**
4115
** This routine is intended for use in custom [VFS] implementations
4116
** only. It is not a general-purpose interface.
4117
** The argument sqlite3_file_object(X) must be a filename pointer that
4118
** has been passed into [sqlite3_vfs].xOpen method where the
4119
** flags parameter to xOpen contains one of the bits
4120
** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use
4121
** of this routine results in undefined and probably undesirable
4122
** behavior.
4123
*/
4124
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
4125
4126
/*
4127
** CAPI3REF: Create and Destroy VFS Filenames
4128
**
4129
** These interfaces are provided for use by [VFS shim] implementations and
4130
** are not useful outside of that context.
4131
**
4132
** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
4133
** database filename D with corresponding journal file J and WAL file W and
4134
** an array P of N URI Key/Value pairs. The result from
4135
** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
4136
** is safe to pass to routines like:
4137
** <ul>
4138
** <li> [sqlite3_uri_parameter()],
4139
** <li> [sqlite3_uri_boolean()],
4140
** <li> [sqlite3_uri_int64()],
4141
** <li> [sqlite3_uri_key()],
4142
** <li> [sqlite3_filename_database()],
4143
** <li> [sqlite3_filename_journal()], or
4144
** <li> [sqlite3_filename_wal()].
4145
** </ul>
4146
** If a memory allocation error occurs, sqlite3_create_filename() might
4147
** return a NULL pointer. The memory obtained from sqlite3_create_filename(X)
4148
** must be released by a corresponding call to sqlite3_free_filename(Y).
4149
**
4150
** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
4151
** of 2*N pointers to strings. Each pair of pointers in this array corresponds
4152
** to a key and value for a query parameter. The P parameter may be a NULL
4153
** pointer if N is zero. None of the 2*N pointers in the P array may be
4154
** NULL pointers and key pointers should not be empty strings.
4155
** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
4156
** be NULL pointers, though they can be empty strings.
4157
**
4158
** The sqlite3_free_filename(Y) routine releases a memory allocation
4159
** previously obtained from sqlite3_create_filename(). Invoking
4160
** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
4161
**
4162
** If the Y parameter to sqlite3_free_filename(Y) is anything other
4163
** than a NULL pointer or a pointer previously acquired from
4164
** sqlite3_create_filename(), then bad things such as heap
4165
** corruption or segfaults may occur. The value Y should not be
4166
** used again after sqlite3_free_filename(Y) has been called. This means
4167
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
4168
** then the corresponding [sqlite3_module.xClose() method should also be
4169
** invoked prior to calling sqlite3_free_filename(Y).
4170
*/
4171
SQLITE_API sqlite3_filename sqlite3_create_filename(
4172
const char *zDatabase,
4173
const char *zJournal,
4174
const char *zWal,
4175
int nParam,
4176
const char **azParam
4177
);
4178
SQLITE_API void sqlite3_free_filename(sqlite3_filename);
4179
4180
/*
4181
** CAPI3REF: Error Codes And Messages
4182
** METHOD: sqlite3
4183
**
4184
** ^If the most recent sqlite3_* API call associated with
4185
** [database connection] D failed, then the sqlite3_errcode(D) interface
4186
** returns the numeric [result code] or [extended result code] for that
4187
** API call.
4188
** ^The sqlite3_extended_errcode()
4189
** interface is the same except that it always returns the
4190
** [extended result code] even when extended result codes are
4191
** disabled.
4192
**
4193
** The values returned by sqlite3_errcode() and/or
4194
** sqlite3_extended_errcode() might change with each API call.
4195
** Except, there are some interfaces that are guaranteed to never
4196
** change the value of the error code. The error-code preserving
4197
** interfaces include the following:
4198
**
4199
** <ul>
4200
** <li> sqlite3_errcode()
4201
** <li> sqlite3_extended_errcode()
4202
** <li> sqlite3_errmsg()
4203
** <li> sqlite3_errmsg16()
4204
** <li> sqlite3_error_offset()
4205
** <li> sqlite3_db_handle()
4206
** </ul>
4207
**
4208
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
4209
** text that describes the error, as either UTF-8 or UTF-16 respectively,
4210
** or NULL if no error message is available.
4211
** (See how SQLite handles [invalid UTF] for exceptions to this rule.)
4212
** ^(Memory to hold the error message string is managed internally.
4213
** The application does not need to worry about freeing the result.
4214
** However, the error string might be overwritten or deallocated by
4215
** subsequent calls to other SQLite interface functions.)^
4216
**
4217
** ^The sqlite3_errstr(E) interface returns the English-language text
4218
** that describes the [result code] E, as UTF-8, or NULL if E is not a
4219
** result code for which a text error message is available.
4220
** ^(Memory to hold the error message string is managed internally
4221
** and must not be freed by the application)^.
4222
**
4223
** ^If the most recent error references a specific token in the input
4224
** SQL, the sqlite3_error_offset() interface returns the byte offset
4225
** of the start of that token. ^The byte offset returned by
4226
** sqlite3_error_offset() assumes that the input SQL is UTF-8.
4227
** ^If the most recent error does not reference a specific token in the input
4228
** SQL, then the sqlite3_error_offset() function returns -1.
4229
**
4230
** When the serialized [threading mode] is in use, it might be the
4231
** case that a second error occurs on a separate thread in between
4232
** the time of the first error and the call to these interfaces.
4233
** When that happens, the second error will be reported since these
4234
** interfaces always report the most recent result. To avoid
4235
** this, each thread can obtain exclusive use of the [database connection] D
4236
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
4237
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
4238
** all calls to the interfaces listed here are completed.
4239
**
4240
** If an interface fails with SQLITE_MISUSE, that means the interface
4241
** was invoked incorrectly by the application. In that case, the
4242
** error code and message may or may not be set.
4243
*/
4244
SQLITE_API int sqlite3_errcode(sqlite3 *db);
4245
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
4246
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
4247
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
4248
SQLITE_API const char *sqlite3_errstr(int);
4249
SQLITE_API int sqlite3_error_offset(sqlite3 *db);
4250
4251
/*
4252
** CAPI3REF: Set Error Code And Message
4253
** METHOD: sqlite3
4254
**
4255
** Set the error code of the database handle passed as the first argument
4256
** to errcode, and the error message to a copy of nul-terminated string
4257
** zErrMsg. If zErrMsg is passed NULL, then the error message is set to
4258
** the default message associated with the supplied error code. Subsequent
4259
** calls to [sqlite3_errcode()] and [sqlite3_errmsg()] and similar will
4260
** return the values set by this routine in place of what was previously
4261
** set by SQLite itself.
4262
**
4263
** This function returns SQLITE_OK if the error code and error message are
4264
** successfully set, SQLITE_NOMEM if an OOM occurs, and SQLITE_MISUSE if
4265
** the database handle is NULL or invalid.
4266
**
4267
** The error code and message set by this routine remains in effect until
4268
** they are changed, either by another call to this routine or until they are
4269
** changed to by SQLite itself to reflect the result of some subsquent
4270
** API call.
4271
**
4272
** This function is intended for use by SQLite extensions or wrappers. The
4273
** idea is that an extension or wrapper can use this routine to set error
4274
** messages and error codes and thus behave more like a core SQLite
4275
** feature from the point of view of an application.
4276
*/
4277
SQLITE_API int sqlite3_set_errmsg(sqlite3 *db, int errcode, const char *zErrMsg);
4278
4279
/*
4280
** CAPI3REF: Prepared Statement Object
4281
** KEYWORDS: {prepared statement} {prepared statements}
4282
**
4283
** An instance of this object represents a single SQL statement that
4284
** has been compiled into binary form and is ready to be evaluated.
4285
**
4286
** Think of each SQL statement as a separate computer program. The
4287
** original SQL text is source code. A prepared statement object
4288
** is the compiled object code. All SQL must be converted into a
4289
** prepared statement before it can be run.
4290
**
4291
** The life-cycle of a prepared statement object usually goes like this:
4292
**
4293
** <ol>
4294
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
4295
** <li> Bind values to [parameters] using the sqlite3_bind_*()
4296
** interfaces.
4297
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
4298
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
4299
** to step 2. Do this zero or more times.
4300
** <li> Destroy the object using [sqlite3_finalize()].
4301
** </ol>
4302
*/
4303
typedef struct sqlite3_stmt sqlite3_stmt;
4304
4305
/*
4306
** CAPI3REF: Run-time Limits
4307
** METHOD: sqlite3
4308
**
4309
** ^(This interface allows the size of various constructs to be limited
4310
** on a connection by connection basis. The first parameter is the
4311
** [database connection] whose limit is to be set or queried. The
4312
** second parameter is one of the [limit categories] that define a
4313
** class of constructs to be size limited. The third parameter is the
4314
** new limit for that construct.)^
4315
**
4316
** ^If the new limit is a negative number, the limit is unchanged.
4317
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
4318
** [limits | hard upper bound]
4319
** set at compile-time by a C preprocessor macro called
4320
** [limits | SQLITE_MAX_<i>NAME</i>].
4321
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
4322
** ^Attempts to increase a limit above its hard upper bound are
4323
** silently truncated to the hard upper bound.
4324
**
4325
** ^Regardless of whether or not the limit was changed, the
4326
** [sqlite3_limit()] interface returns the prior value of the limit.
4327
** ^Hence, to find the current value of a limit without changing it,
4328
** simply invoke this interface with the third parameter set to -1.
4329
**
4330
** Run-time limits are intended for use in applications that manage
4331
** both their own internal database and also databases that are controlled
4332
** by untrusted external sources. An example application might be a
4333
** web browser that has its own databases for storing history and
4334
** separate databases controlled by JavaScript applications downloaded
4335
** off the Internet. The internal databases can be given the
4336
** large, default limits. Databases managed by external sources can
4337
** be given much smaller limits designed to prevent a denial of service
4338
** attack. Developers might also want to use the [sqlite3_set_authorizer()]
4339
** interface to further control untrusted SQL. The size of the database
4340
** created by an untrusted script can be contained using the
4341
** [max_page_count] [PRAGMA].
4342
**
4343
** New run-time limit categories may be added in future releases.
4344
*/
4345
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
4346
4347
/*
4348
** CAPI3REF: Run-Time Limit Categories
4349
** KEYWORDS: {limit category} {*limit categories}
4350
**
4351
** These constants define various performance limits
4352
** that can be lowered at run-time using [sqlite3_limit()].
4353
** A concise description of these limits follows, and additional information
4354
** is available at [limits | Limits in SQLite].
4355
**
4356
** <dl>
4357
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
4358
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
4359
**
4360
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
4361
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
4362
**
4363
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
4364
** <dd>The maximum number of columns in a table definition or in the
4365
** result set of a [SELECT] or the maximum number of columns in an index
4366
** or in an ORDER BY or GROUP BY clause.</dd>)^
4367
**
4368
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
4369
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
4370
**
4371
** [[SQLITE_LIMIT_PARSER_DEPTH]] ^(<dt>SQLITE_LIMIT_PARSER_DEPTH</dt>
4372
** <dd>The maximum depth of the LALR(1) parser stack used to analyze
4373
** input SQL statements.</dd>)^
4374
**
4375
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
4376
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
4377
**
4378
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
4379
** <dd>The maximum number of instructions in a virtual machine program
4380
** used to implement an SQL statement. If [sqlite3_prepare_v2()] or
4381
** the equivalent tries to allocate space for more than this many opcodes
4382
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
4383
**
4384
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
4385
** <dd>The maximum number of arguments on a function.</dd>)^
4386
**
4387
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
4388
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
4389
**
4390
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
4391
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
4392
** <dd>The maximum length of the pattern argument to the [LIKE] or
4393
** [GLOB] operators.</dd>)^
4394
**
4395
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
4396
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
4397
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
4398
**
4399
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
4400
** <dd>The maximum depth of recursion for triggers.</dd>)^
4401
**
4402
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
4403
** <dd>The maximum number of auxiliary worker threads that a single
4404
** [prepared statement] may start.</dd>)^
4405
** </dl>
4406
*/
4407
#define SQLITE_LIMIT_LENGTH 0
4408
#define SQLITE_LIMIT_SQL_LENGTH 1
4409
#define SQLITE_LIMIT_COLUMN 2
4410
#define SQLITE_LIMIT_EXPR_DEPTH 3
4411
#define SQLITE_LIMIT_COMPOUND_SELECT 4
4412
#define SQLITE_LIMIT_VDBE_OP 5
4413
#define SQLITE_LIMIT_FUNCTION_ARG 6
4414
#define SQLITE_LIMIT_ATTACHED 7
4415
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
4416
#define SQLITE_LIMIT_VARIABLE_NUMBER 9
4417
#define SQLITE_LIMIT_TRIGGER_DEPTH 10
4418
#define SQLITE_LIMIT_WORKER_THREADS 11
4419
#define SQLITE_LIMIT_PARSER_DEPTH 12
4420
4421
/*
4422
** CAPI3REF: Prepare Flags
4423
**
4424
** These constants define various flags that can be passed into the
4425
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4426
** [sqlite3_prepare16_v3()] interfaces.
4427
**
4428
** New flags may be added in future releases of SQLite.
4429
**
4430
** <dl>
4431
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4432
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4433
** that the prepared statement will be retained for a long time and
4434
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4435
** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4436
** be used just once or at most a few times and then destroyed using
4437
** [sqlite3_finalize()] relatively soon. The current implementation acts
4438
** on this hint by avoiding the use of [lookaside memory] so as not to
4439
** deplete the limited store of lookaside memory. Future versions of
4440
** SQLite may act on this hint differently.
4441
**
4442
** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4443
** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4444
** to be required for any prepared statement that wanted to use the
4445
** [sqlite3_normalized_sql()] interface. However, the
4446
** [sqlite3_normalized_sql()] interface is now available to all
4447
** prepared statements, regardless of whether or not they use this
4448
** flag.
4449
**
4450
** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4451
** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4452
** to return an error (error code SQLITE_ERROR) if the statement uses
4453
** any virtual tables.
4454
**
4455
** [[SQLITE_PREPARE_DONT_LOG]] <dt>SQLITE_PREPARE_DONT_LOG</dt>
4456
** <dd>The SQLITE_PREPARE_DONT_LOG flag prevents SQL compiler
4457
** errors from being sent to the error log defined by
4458
** [SQLITE_CONFIG_LOG]. This can be used, for example, to do test
4459
** compiles to see if some SQL syntax is well-formed, without generating
4460
** messages on the global error log when it is not. If the test compile
4461
** fails, the sqlite3_prepare_v3() call returns the same error indications
4462
** with or without this flag; it just omits the call to [sqlite3_log()] that
4463
** logs the error.
4464
**
4465
** [[SQLITE_PREPARE_FROM_DDL]] <dt>SQLITE_PREPARE_FROM_DDL</dt>
4466
** <dd>The SQLITE_PREPARE_FROM_DDL flag causes the SQL compiler to enforce
4467
** security constraints that would otherwise only be enforced when parsing
4468
** the database schema. In other words, the SQLITE_PREPARE_FROM_DDL flag
4469
** causes the SQL compiler to treat the SQL statement being prepared as if
4470
** it had come from an attacker. When SQLITE_PREPARE_FROM_DDL is used and
4471
** [SQLITE_DBCONFIG_TRUSTED_SCHEMA] is off, SQL functions may only be called
4472
** if they are tagged with [SQLITE_INNOCUOUS] and virtual tables may only
4473
** be used if they are tagged with [SQLITE_VTAB_INNOCUOUS]. Best practice
4474
** is to use the SQLITE_PREPARE_FROM_DDL option when preparing any SQL that
4475
** is derived from parts of the database schema. In particular, virtual
4476
** table implementations that run SQL statements that are derived from
4477
** arguments to their CREATE VIRTUAL TABLE statement should always use
4478
** [sqlite3_prepare_v3()] and set the SQLITE_PREPARE_FROM_DDL flag to
4479
** prevent bypass of the [SQLITE_DBCONFIG_TRUSTED_SCHEMA] security checks.
4480
** </dl>
4481
*/
4482
#define SQLITE_PREPARE_PERSISTENT 0x01
4483
#define SQLITE_PREPARE_NORMALIZE 0x02
4484
#define SQLITE_PREPARE_NO_VTAB 0x04
4485
#define SQLITE_PREPARE_DONT_LOG 0x10
4486
#define SQLITE_PREPARE_FROM_DDL 0x20
4487
4488
/*
4489
** CAPI3REF: Compiling An SQL Statement
4490
** KEYWORDS: {SQL statement compiler}
4491
** METHOD: sqlite3
4492
** CONSTRUCTOR: sqlite3_stmt
4493
**
4494
** To execute an SQL statement, it must first be compiled into a byte-code
4495
** program using one of these routines. Or, in other words, these routines
4496
** are constructors for the [prepared statement] object.
4497
**
4498
** The preferred routine to use is [sqlite3_prepare_v2()]. The
4499
** [sqlite3_prepare()] interface is legacy and should be avoided.
4500
** [sqlite3_prepare_v3()] has an extra
4501
** [SQLITE_PREPARE_FROM_DDL|"prepFlags" option] that is sometimes
4502
** needed for special purpose or to pass along security restrictions.
4503
**
4504
** The use of the UTF-8 interfaces is preferred, as SQLite currently
4505
** does all parsing using UTF-8. The UTF-16 interfaces are provided
4506
** as a convenience. The UTF-16 interfaces work by converting the
4507
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4508
**
4509
** The first argument, "db", is a [database connection] obtained from a
4510
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4511
** [sqlite3_open16()]. The database connection must not have been closed.
4512
**
4513
** The second argument, "zSql", is the statement to be compiled, encoded
4514
** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(),
4515
** and sqlite3_prepare_v3()
4516
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4517
** and sqlite3_prepare16_v3() use UTF-16.
4518
**
4519
** ^If the nByte argument is negative, then zSql is read up to the
4520
** first zero terminator. ^If nByte is positive, then it is the maximum
4521
** number of bytes read from zSql. When nByte is positive, zSql is read
4522
** up to the first zero terminator or until the nByte bytes have been read,
4523
** whichever comes first. ^If nByte is zero, then no prepared
4524
** statement is generated.
4525
** If the caller knows that the supplied string is nul-terminated, then
4526
** there is a small performance advantage to passing an nByte parameter that
4527
** is the number of bytes in the input string <i>including</i>
4528
** the nul-terminator.
4529
** Note that nByte measures the length of the input in bytes, not
4530
** characters, even for the UTF-16 interfaces.
4531
**
4532
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4533
** past the end of the first SQL statement in zSql. These routines only
4534
** compile the first statement in zSql, so *pzTail is left pointing to
4535
** what remains uncompiled.
4536
**
4537
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4538
** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
4539
** to NULL. ^If the input text contains no SQL (if the input is an empty
4540
** string or a comment) then *ppStmt is set to NULL.
4541
** The calling procedure is responsible for deleting the compiled
4542
** SQL statement using [sqlite3_finalize()] after it has finished with it.
4543
** ppStmt may not be NULL.
4544
**
4545
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4546
** otherwise an [error code] is returned.
4547
**
4548
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4549
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4550
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4551
** are retained for backwards compatibility, but their use is discouraged.
4552
** ^In the "vX" interfaces, the prepared statement
4553
** that is returned (the [sqlite3_stmt] object) contains a copy of the
4554
** original SQL text. This causes the [sqlite3_step()] interface to
4555
** behave differently in three ways:
4556
**
4557
** <ol>
4558
** <li>
4559
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4560
** always used to do, [sqlite3_step()] will automatically recompile the SQL
4561
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4562
** retries will occur before sqlite3_step() gives up and returns an error.
4563
** </li>
4564
**
4565
** <li>
4566
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4567
** [error codes] or [extended error codes]. ^The legacy behavior was that
4568
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4569
** and the application would have to make a second call to [sqlite3_reset()]
4570
** in order to find the underlying cause of the problem. With the "v2" prepare
4571
** interfaces, the underlying reason for the error is returned immediately.
4572
** </li>
4573
**
4574
** <li>
4575
** ^If the specific value bound to a [parameter | host parameter] in the
4576
** WHERE clause might influence the choice of query plan for a statement,
4577
** then the statement will be automatically recompiled, as if there had been
4578
** a schema change, on the first [sqlite3_step()] call following any change
4579
** to the [sqlite3_bind_text | bindings] of that [parameter].
4580
** ^The specific value of a WHERE-clause [parameter] might influence the
4581
** choice of query plan if the parameter is the left-hand side of a [LIKE]
4582
** or [GLOB] operator or if the parameter is compared to an indexed column
4583
** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4584
** </li>
4585
** </ol>
4586
**
4587
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4588
** the extra prepFlags parameter, which is a bit array consisting of zero or
4589
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The
4590
** sqlite3_prepare_v2() interface works exactly the same as
4591
** sqlite3_prepare_v3() with a zero prepFlags parameter.
4592
*/
4593
SQLITE_API int sqlite3_prepare(
4594
sqlite3 *db, /* Database handle */
4595
const char *zSql, /* SQL statement, UTF-8 encoded */
4596
int nByte, /* Maximum length of zSql in bytes. */
4597
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4598
const char **pzTail /* OUT: Pointer to unused portion of zSql */
4599
);
4600
SQLITE_API int sqlite3_prepare_v2(
4601
sqlite3 *db, /* Database handle */
4602
const char *zSql, /* SQL statement, UTF-8 encoded */
4603
int nByte, /* Maximum length of zSql in bytes. */
4604
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4605
const char **pzTail /* OUT: Pointer to unused portion of zSql */
4606
);
4607
SQLITE_API int sqlite3_prepare_v3(
4608
sqlite3 *db, /* Database handle */
4609
const char *zSql, /* SQL statement, UTF-8 encoded */
4610
int nByte, /* Maximum length of zSql in bytes. */
4611
unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4612
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4613
const char **pzTail /* OUT: Pointer to unused portion of zSql */
4614
);
4615
SQLITE_API int sqlite3_prepare16(
4616
sqlite3 *db, /* Database handle */
4617
const void *zSql, /* SQL statement, UTF-16 encoded */
4618
int nByte, /* Maximum length of zSql in bytes. */
4619
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4620
const void **pzTail /* OUT: Pointer to unused portion of zSql */
4621
);
4622
SQLITE_API int sqlite3_prepare16_v2(
4623
sqlite3 *db, /* Database handle */
4624
const void *zSql, /* SQL statement, UTF-16 encoded */
4625
int nByte, /* Maximum length of zSql in bytes. */
4626
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4627
const void **pzTail /* OUT: Pointer to unused portion of zSql */
4628
);
4629
SQLITE_API int sqlite3_prepare16_v3(
4630
sqlite3 *db, /* Database handle */
4631
const void *zSql, /* SQL statement, UTF-16 encoded */
4632
int nByte, /* Maximum length of zSql in bytes. */
4633
unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4634
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
4635
const void **pzTail /* OUT: Pointer to unused portion of zSql */
4636
);
4637
4638
/*
4639
** CAPI3REF: Retrieving Statement SQL
4640
** METHOD: sqlite3_stmt
4641
**
4642
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4643
** SQL text used to create [prepared statement] P if P was
4644
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4645
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4646
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4647
** string containing the SQL text of prepared statement P with
4648
** [bound parameters] expanded.
4649
** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4650
** string containing the normalized SQL text of prepared statement P. The
4651
** semantics used to normalize a SQL statement are unspecified and subject
4652
** to change. At a minimum, literal values will be replaced with suitable
4653
** placeholders.
4654
**
4655
** ^(For example, if a prepared statement is created using the SQL
4656
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4657
** and parameter :xyz is unbound, then sqlite3_sql() will return
4658
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4659
** will return "SELECT 2345,NULL".)^
4660
**
4661
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4662
** is available to hold the result, or if the result would exceed the
4663
** maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4664
**
4665
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4666
** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time
4667
** option causes sqlite3_expanded_sql() to always return NULL.
4668
**
4669
** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4670
** are managed by SQLite and are automatically freed when the prepared
4671
** statement is finalized.
4672
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4673
** is obtained from [sqlite3_malloc()] and must be freed by the application
4674
** by passing it to [sqlite3_free()].
4675
**
4676
** ^The sqlite3_normalized_sql() interface is only available if
4677
** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4678
*/
4679
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4680
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4681
#ifdef SQLITE_ENABLE_NORMALIZE
4682
SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4683
#endif
4684
4685
/*
4686
** CAPI3REF: Determine If An SQL Statement Writes The Database
4687
** METHOD: sqlite3_stmt
4688
**
4689
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4690
** and only if the [prepared statement] X makes no direct changes to
4691
** the content of the database file.
4692
**
4693
** Note that [application-defined SQL functions] or
4694
** [virtual tables] might change the database indirectly as a side effect.
4695
** ^(For example, if an application defines a function "eval()" that
4696
** calls [sqlite3_exec()], then the following SQL statement would
4697
** change the database file through side-effects:
4698
**
4699
** <blockquote><pre>
4700
** SELECT eval('DELETE FROM t1') FROM t2;
4701
** </pre></blockquote>
4702
**
4703
** But because the [SELECT] statement does not change the database file
4704
** directly, sqlite3_stmt_readonly() would still return true.)^
4705
**
4706
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4707
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4708
** since the statements themselves do not actually modify the database but
4709
** rather they control the timing of when other statements modify the
4710
** database. ^The [ATTACH] and [DETACH] statements also cause
4711
** sqlite3_stmt_readonly() to return true since, while those statements
4712
** change the configuration of a database connection, they do not make
4713
** changes to the content of the database files on disk.
4714
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4715
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4716
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4717
** sqlite3_stmt_readonly() returns false for those commands.
4718
**
4719
** ^This routine returns false if there is any possibility that the
4720
** statement might change the database file. ^A false return does
4721
** not guarantee that the statement will change the database file.
4722
** ^For example, an UPDATE statement might have a WHERE clause that
4723
** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4724
** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4725
** read-only no-op if the table already exists, but
4726
** sqlite3_stmt_readonly() still returns false for such a statement.
4727
**
4728
** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4729
** statement, then sqlite3_stmt_readonly(X) returns the same value as
4730
** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4731
*/
4732
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4733
4734
/*
4735
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4736
** METHOD: sqlite3_stmt
4737
**
4738
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4739
** prepared statement S is an EXPLAIN statement, or 2 if the
4740
** statement S is an EXPLAIN QUERY PLAN.
4741
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4742
** an ordinary statement or a NULL pointer.
4743
*/
4744
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4745
4746
/*
4747
** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement
4748
** METHOD: sqlite3_stmt
4749
**
4750
** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
4751
** setting for [prepared statement] S. If E is zero, then S becomes
4752
** a normal prepared statement. If E is 1, then S behaves as if
4753
** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if
4754
** its SQL text began with "[EXPLAIN QUERY PLAN]".
4755
**
4756
** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
4757
** SQLite tries to avoid a reprepare, but a reprepare might be necessary
4758
** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.
4759
**
4760
** Because of the potential need to reprepare, a call to
4761
** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
4762
** reprepared because it was created using [sqlite3_prepare()] instead of
4763
** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and
4764
** hence has no saved SQL text with which to reprepare.
4765
**
4766
** Changing the explain setting for a prepared statement does not change
4767
** the original SQL text for the statement. Hence, if the SQL text originally
4768
** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
4769
** is called to convert the statement into an ordinary statement, the EXPLAIN
4770
** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
4771
** output, even though the statement now acts like a normal SQL statement.
4772
**
4773
** This routine returns SQLITE_OK if the explain mode is successfully
4774
** changed, or an error code if the explain mode could not be changed.
4775
** The explain mode cannot be changed while a statement is active.
4776
** Hence, it is good practice to call [sqlite3_reset(S)]
4777
** immediately prior to calling sqlite3_stmt_explain(S,E).
4778
*/
4779
SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
4780
4781
/*
4782
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4783
** METHOD: sqlite3_stmt
4784
**
4785
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4786
** [prepared statement] S has been stepped at least once using
4787
** [sqlite3_step(S)] but has neither run to completion (returned
4788
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4789
** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
4790
** interface returns false if S is a NULL pointer. If S is not a
4791
** NULL pointer and is not a pointer to a valid [prepared statement]
4792
** object, then the behavior is undefined and probably undesirable.
4793
**
4794
** This interface can be used in combination [sqlite3_next_stmt()]
4795
** to locate all prepared statements associated with a database
4796
** connection that are in need of being reset. This can be used,
4797
** for example, in diagnostic routines to search for prepared
4798
** statements that are holding a transaction open.
4799
*/
4800
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4801
4802
/*
4803
** CAPI3REF: Dynamically Typed Value Object
4804
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4805
**
4806
** SQLite uses the sqlite3_value object to represent all values
4807
** that can be stored in a database table. SQLite uses dynamic typing
4808
** for the values it stores. ^Values stored in sqlite3_value objects
4809
** can be integers, floating point values, strings, BLOBs, or NULL.
4810
**
4811
** An sqlite3_value object may be either "protected" or "unprotected".
4812
** Some interfaces require a protected sqlite3_value. Other interfaces
4813
** will accept either a protected or an unprotected sqlite3_value.
4814
** Every interface that accepts sqlite3_value arguments specifies
4815
** whether or not it requires a protected sqlite3_value. The
4816
** [sqlite3_value_dup()] interface can be used to construct a new
4817
** protected sqlite3_value from an unprotected sqlite3_value.
4818
**
4819
** The terms "protected" and "unprotected" refer to whether or not
4820
** a mutex is held. An internal mutex is held for a protected
4821
** sqlite3_value object but no mutex is held for an unprotected
4822
** sqlite3_value object. If SQLite is compiled to be single-threaded
4823
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4824
** or if SQLite is run in one of reduced mutex modes
4825
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4826
** then there is no distinction between protected and unprotected
4827
** sqlite3_value objects and they can be used interchangeably. However,
4828
** for maximum code portability it is recommended that applications
4829
** still make the distinction between protected and unprotected
4830
** sqlite3_value objects even when not strictly required.
4831
**
4832
** ^The sqlite3_value objects that are passed as parameters into the
4833
** implementation of [application-defined SQL functions] are protected.
4834
** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4835
** are protected.
4836
** ^The sqlite3_value object returned by
4837
** [sqlite3_column_value()] is unprotected.
4838
** Unprotected sqlite3_value objects may only be used as arguments
4839
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4840
** [sqlite3_value_dup()].
4841
** The [sqlite3_value_blob | sqlite3_value_type()] family of
4842
** interfaces require protected sqlite3_value objects.
4843
*/
4844
typedef struct sqlite3_value sqlite3_value;
4845
4846
/*
4847
** CAPI3REF: SQL Function Context Object
4848
**
4849
** The context in which an SQL function executes is stored in an
4850
** sqlite3_context object. ^A pointer to an sqlite3_context object
4851
** is always the first parameter to [application-defined SQL functions].
4852
** The application-defined SQL function implementation will pass this
4853
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4854
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4855
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4856
** and/or [sqlite3_set_auxdata()].
4857
*/
4858
typedef struct sqlite3_context sqlite3_context;
4859
4860
/*
4861
** CAPI3REF: Binding Values To Prepared Statements
4862
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4863
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4864
** METHOD: sqlite3_stmt
4865
**
4866
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4867
** literals may be replaced by a [parameter] that matches one of the following
4868
** templates:
4869
**
4870
** <ul>
4871
** <li> ?
4872
** <li> ?NNN
4873
** <li> :VVV
4874
** <li> @VVV
4875
** <li> $VVV
4876
** </ul>
4877
**
4878
** In the templates above, NNN represents an integer literal,
4879
** and VVV represents an alphanumeric identifier.)^ ^The values of these
4880
** parameters (also called "host parameter names" or "SQL parameters")
4881
** can be set using the sqlite3_bind_*() routines defined here.
4882
**
4883
** ^The first argument to the sqlite3_bind_*() routines is always
4884
** a pointer to the [sqlite3_stmt] object returned from
4885
** [sqlite3_prepare_v2()] or its variants.
4886
**
4887
** ^The second argument is the index of the SQL parameter to be set.
4888
** ^The leftmost SQL parameter has an index of 1. ^When the same named
4889
** SQL parameter is used more than once, second and subsequent
4890
** occurrences have the same index as the first occurrence.
4891
** ^The index for named parameters can be looked up using the
4892
** [sqlite3_bind_parameter_index()] API if desired. ^The index
4893
** for "?NNN" parameters is the value of NNN.
4894
** ^The NNN value must be between 1 and the [sqlite3_limit()]
4895
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4896
**
4897
** ^The third argument is the value to bind to the parameter.
4898
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4899
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4900
** is ignored and the end result is the same as sqlite3_bind_null().
4901
** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4902
** it should be a pointer to well-formed UTF8 text.
4903
** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4904
** it should be a pointer to well-formed UTF16 text.
4905
** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4906
** it should be a pointer to a well-formed unicode string that is
4907
** either UTF8 if the sixth parameter is SQLITE_UTF8 or SQLITE_UTF8_ZT,
4908
** or UTF16 otherwise.
4909
**
4910
** [[byte-order determination rules]] ^The byte-order of
4911
** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4912
** found in the first character, which is removed, or in the absence of a BOM
4913
** the byte order is the native byte order of the host
4914
** machine for sqlite3_bind_text16() or the byte order specified in
4915
** the 6th parameter for sqlite3_bind_text64().)^
4916
** ^If UTF16 input text contains invalid unicode
4917
** characters, then SQLite might change those invalid characters
4918
** into the unicode replacement character: U+FFFD.
4919
**
4920
** ^(In those routines that have a fourth argument, its value is the
4921
** number of bytes in the parameter. To be clear: the value is the
4922
** number of <u>bytes</u> in the value, not the number of characters.)^
4923
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4924
** is negative, then the length of the string is
4925
** the number of bytes up to the first zero terminator.
4926
** If the fourth parameter to sqlite3_bind_blob() is negative, then
4927
** the behavior is undefined.
4928
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4929
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4930
** that parameter must be the byte offset
4931
** where the NUL terminator would occur assuming the string were NUL
4932
** terminated. If any NUL characters occur at byte offsets less than
4933
** the value of the fourth parameter then the resulting string value will
4934
** contain embedded NULs. The result of expressions involving strings
4935
** with embedded NULs is undefined.
4936
**
4937
** ^The fifth argument to the BLOB and string binding interfaces controls
4938
** or indicates the lifetime of the object referenced by the third parameter.
4939
** These three options exist:
4940
** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4941
** with it may be passed. ^It is called to dispose of the BLOB or string even
4942
** if the call to the bind API fails, except the destructor is not called if
4943
** the third parameter is a NULL pointer or the fourth parameter is negative.
4944
** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that
4945
** the application remains responsible for disposing of the object. ^In this
4946
** case, the object and the provided pointer to it must remain valid until
4947
** either the prepared statement is finalized or the same SQL parameter is
4948
** bound to something else, whichever occurs sooner.
4949
** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4950
** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4951
** object and pointer to it must remain valid until then. ^SQLite will then
4952
** manage the lifetime of its private copy.
4953
**
4954
** ^The sixth argument (the E argument)
4955
** to sqlite3_bind_text64(S,K,Z,N,D,E) must be one of
4956
** [SQLITE_UTF8], [SQLITE_UTF8_ZT], [SQLITE_UTF16], [SQLITE_UTF16BE],
4957
** or [SQLITE_UTF16LE] to specify the encoding of the text in the
4958
** third parameter, Z. The special value [SQLITE_UTF8_ZT] means that the
4959
** string argument is both UTF-8 encoded and is zero-terminated. In other
4960
** words, SQLITE_UTF8_ZT means that the Z array is allocated to hold at
4961
** least N+1 bytes and that the Z&#91;N&#93; byte is zero. If
4962
** the E argument to sqlite3_bind_text64(S,K,Z,N,D,E) is not one of the
4963
** allowed values shown above, or if the text encoding is different
4964
** from the encoding specified by the sixth parameter, then the behavior
4965
** is undefined.
4966
**
4967
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4968
** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
4969
** (just an integer to hold its size) while it is being processed.
4970
** Zeroblobs are intended to serve as placeholders for BLOBs whose
4971
** content is later written using
4972
** [sqlite3_blob_open | incremental BLOB I/O] routines.
4973
** ^A negative value for the zeroblob results in a zero-length BLOB.
4974
**
4975
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4976
** [prepared statement] S to have an SQL value of NULL, but to also be
4977
** associated with the pointer P of type T. ^D is either a NULL pointer or
4978
** a pointer to a destructor function for P. ^SQLite will invoke the
4979
** destructor D with a single argument of P when it is finished using
4980
** P, even if the call to sqlite3_bind_pointer() fails. Due to a
4981
** historical design quirk, results are undefined if D is
4982
** SQLITE_TRANSIENT. The T parameter should be a static string,
4983
** preferably a string literal. The sqlite3_bind_pointer() routine is
4984
** part of the [pointer passing interface] added for SQLite 3.20.0.
4985
**
4986
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4987
** for the [prepared statement] or with a prepared statement for which
4988
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4989
** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
4990
** routine is passed a [prepared statement] that has been finalized, the
4991
** result is undefined and probably harmful.
4992
**
4993
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4994
** ^Unbound parameters are interpreted as NULL.
4995
**
4996
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4997
** [error code] if anything goes wrong.
4998
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4999
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
5000
** [SQLITE_MAX_LENGTH].
5001
** ^[SQLITE_RANGE] is returned if the parameter
5002
** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
5003
**
5004
** See also: [sqlite3_bind_parameter_count()],
5005
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
5006
*/
5007
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
5008
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
5009
void(*)(void*));
5010
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
5011
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
5012
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
5013
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
5014
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
5015
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
5016
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
5017
void(*)(void*), unsigned char encoding);
5018
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
5019
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
5020
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
5021
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
5022
5023
/*
5024
** CAPI3REF: Number Of SQL Parameters
5025
** METHOD: sqlite3_stmt
5026
**
5027
** ^This routine can be used to find the number of [SQL parameters]
5028
** in a [prepared statement]. SQL parameters are tokens of the
5029
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
5030
** placeholders for values that are [sqlite3_bind_blob | bound]
5031
** to the parameters at a later time.
5032
**
5033
** ^(This routine actually returns the index of the largest (rightmost)
5034
** parameter. For all forms except ?NNN, this will correspond to the
5035
** number of unique parameters. If parameters of the ?NNN form are used,
5036
** there may be gaps in the list.)^
5037
**
5038
** See also: [sqlite3_bind_blob|sqlite3_bind()],
5039
** [sqlite3_bind_parameter_name()], and
5040
** [sqlite3_bind_parameter_index()].
5041
*/
5042
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
5043
5044
/*
5045
** CAPI3REF: Name Of A Host Parameter
5046
** METHOD: sqlite3_stmt
5047
**
5048
** ^The sqlite3_bind_parameter_name(P,N) interface returns
5049
** the name of the N-th [SQL parameter] in the [prepared statement] P.
5050
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
5051
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
5052
** respectively.
5053
** In other words, the initial ":" or "$" or "@" or "?"
5054
** is included as part of the name.)^
5055
** ^Parameters of the form "?" without a following integer have no name
5056
** and are referred to as "nameless" or "anonymous parameters".
5057
**
5058
** ^The first host parameter has an index of 1, not 0.
5059
**
5060
** ^If the value N is out of range or if the N-th parameter is
5061
** nameless, then NULL is returned. ^The returned string is
5062
** always in UTF-8 encoding even if the named parameter was
5063
** originally specified as UTF-16 in [sqlite3_prepare16()],
5064
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
5065
**
5066
** See also: [sqlite3_bind_blob|sqlite3_bind()],
5067
** [sqlite3_bind_parameter_count()], and
5068
** [sqlite3_bind_parameter_index()].
5069
*/
5070
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
5071
5072
/*
5073
** CAPI3REF: Index Of A Parameter With A Given Name
5074
** METHOD: sqlite3_stmt
5075
**
5076
** ^Return the index of an SQL parameter given its name. ^The
5077
** index value returned is suitable for use as the second
5078
** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
5079
** is returned if no matching parameter is found. ^The parameter
5080
** name must be given in UTF-8 even if the original statement
5081
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
5082
** [sqlite3_prepare16_v3()].
5083
**
5084
** See also: [sqlite3_bind_blob|sqlite3_bind()],
5085
** [sqlite3_bind_parameter_count()], and
5086
** [sqlite3_bind_parameter_name()].
5087
*/
5088
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
5089
5090
/*
5091
** CAPI3REF: Reset All Bindings On A Prepared Statement
5092
** METHOD: sqlite3_stmt
5093
**
5094
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
5095
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
5096
** ^Use this routine to reset all host parameters to NULL.
5097
*/
5098
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
5099
5100
/*
5101
** CAPI3REF: Number Of Columns In A Result Set
5102
** METHOD: sqlite3_stmt
5103
**
5104
** ^Return the number of columns in the result set returned by the
5105
** [prepared statement]. ^If this routine returns 0, that means the
5106
** [prepared statement] returns no data (for example an [UPDATE]).
5107
** ^However, just because this routine returns a positive number does not
5108
** mean that one or more rows of data will be returned. ^A SELECT statement
5109
** will always have a positive sqlite3_column_count() but depending on the
5110
** WHERE clause constraints and the table content, it might return no rows.
5111
**
5112
** See also: [sqlite3_data_count()]
5113
*/
5114
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
5115
5116
/*
5117
** CAPI3REF: Column Names In A Result Set
5118
** METHOD: sqlite3_stmt
5119
**
5120
** ^These routines return the name assigned to a particular column
5121
** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
5122
** interface returns a pointer to a zero-terminated UTF-8 string
5123
** and sqlite3_column_name16() returns a pointer to a zero-terminated
5124
** UTF-16 string. ^The first parameter is the [prepared statement]
5125
** that implements the [SELECT] statement. ^The second parameter is the
5126
** column number. ^The leftmost column is number 0.
5127
**
5128
** ^The returned string pointer is valid until either the [prepared statement]
5129
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
5130
** reprepared by the first call to [sqlite3_step()] for a particular run
5131
** or until the next call to
5132
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
5133
**
5134
** ^If sqlite3_malloc() fails during the processing of either routine
5135
** (for example during a conversion from UTF-8 to UTF-16) then a
5136
** NULL pointer is returned.
5137
**
5138
** ^The name of a result column is the value of the "AS" clause for
5139
** that column, if there is an AS clause. If there is no AS clause
5140
** then the name of the column is unspecified and may change from
5141
** one release of SQLite to the next.
5142
*/
5143
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
5144
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
5145
5146
/*
5147
** CAPI3REF: Source Of Data In A Query Result
5148
** METHOD: sqlite3_stmt
5149
**
5150
** ^These routines provide a means to determine the database, table, and
5151
** table column that is the origin of a particular result column in a
5152
** [SELECT] statement.
5153
** ^The name of the database or table or column can be returned as
5154
** either a UTF-8 or UTF-16 string. ^The _database_ routines return
5155
** the database name, the _table_ routines return the table name, and
5156
** the origin_ routines return the column name.
5157
** ^The returned string is valid until the [prepared statement] is destroyed
5158
** using [sqlite3_finalize()] or until the statement is automatically
5159
** reprepared by the first call to [sqlite3_step()] for a particular run
5160
** or until the same information is requested
5161
** again in a different encoding.
5162
**
5163
** ^The names returned are the original un-aliased names of the
5164
** database, table, and column.
5165
**
5166
** ^The first argument to these interfaces is a [prepared statement].
5167
** ^These functions return information about the Nth result column returned by
5168
** the statement, where N is the second function argument.
5169
** ^The left-most column is column 0 for these routines.
5170
**
5171
** ^If the Nth column returned by the statement is an expression or
5172
** subquery and is not a column value, then all of these functions return
5173
** NULL. ^These routines might also return NULL if a memory allocation error
5174
** occurs. ^Otherwise, they return the name of the attached database, table,
5175
** or column that query result column was extracted from.
5176
**
5177
** ^As with all other SQLite APIs, those whose names end with "16" return
5178
** UTF-16 encoded strings and the other functions return UTF-8.
5179
**
5180
** ^These APIs are only available if the library was compiled with the
5181
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
5182
**
5183
** If two or more threads call one or more
5184
** [sqlite3_column_database_name | column metadata interfaces]
5185
** for the same [prepared statement] and result column
5186
** at the same time then the results are undefined.
5187
*/
5188
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
5189
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
5190
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
5191
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
5192
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
5193
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
5194
5195
/*
5196
** CAPI3REF: Declared Datatype Of A Query Result
5197
** METHOD: sqlite3_stmt
5198
**
5199
** ^(The first parameter is a [prepared statement].
5200
** If this statement is a [SELECT] statement and the Nth column of the
5201
** returned result set of that [SELECT] is a table column (not an
5202
** expression or subquery) then the declared type of the table
5203
** column is returned.)^ ^If the Nth column of the result set is an
5204
** expression or subquery, then a NULL pointer is returned.
5205
** ^The returned string is always UTF-8 encoded.
5206
**
5207
** ^(For example, given the database schema:
5208
**
5209
** CREATE TABLE t1(c1 VARIANT);
5210
**
5211
** and the following statement to be compiled:
5212
**
5213
** SELECT c1 + 1, c1 FROM t1;
5214
**
5215
** this routine would return the string "VARIANT" for the second result
5216
** column (i==1), and a NULL pointer for the first result column (i==0).)^
5217
**
5218
** ^SQLite uses dynamic run-time typing. ^So just because a column
5219
** is declared to contain a particular type does not mean that the
5220
** data stored in that column is of the declared type. SQLite is
5221
** strongly typed, but the typing is dynamic not static. ^Type
5222
** is associated with individual values, not with the containers
5223
** used to hold those values.
5224
*/
5225
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
5226
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
5227
5228
/*
5229
** CAPI3REF: Evaluate An SQL Statement
5230
** METHOD: sqlite3_stmt
5231
**
5232
** After a [prepared statement] has been prepared using any of
5233
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
5234
** or [sqlite3_prepare16_v3()] or one of the legacy
5235
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
5236
** must be called one or more times to evaluate the statement.
5237
**
5238
** The details of the behavior of the sqlite3_step() interface depend
5239
** on whether the statement was prepared using the newer "vX" interfaces
5240
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
5241
** [sqlite3_prepare16_v2()] or the older legacy
5242
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
5243
** new "vX" interface is recommended for new applications but the legacy
5244
** interface will continue to be supported.
5245
**
5246
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
5247
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
5248
** ^With the "v2" interface, any of the other [result codes] or
5249
** [extended result codes] might be returned as well.
5250
**
5251
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
5252
** database locks it needs to do its job. ^If the statement is a [COMMIT]
5253
** or occurs outside of an explicit transaction, then you can retry the
5254
** statement. If the statement is not a [COMMIT] and occurs within an
5255
** explicit transaction then you should rollback the transaction before
5256
** continuing.
5257
**
5258
** ^[SQLITE_DONE] means that the statement has finished executing
5259
** successfully. sqlite3_step() should not be called again on this virtual
5260
** machine without first calling [sqlite3_reset()] to reset the virtual
5261
** machine back to its initial state.
5262
**
5263
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
5264
** is returned each time a new row of data is ready for processing by the
5265
** caller. The values may be accessed using the [column access functions].
5266
** sqlite3_step() is called again to retrieve the next row of data.
5267
**
5268
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
5269
** violation) has occurred. sqlite3_step() should not be called again on
5270
** the VM. More information may be found by calling [sqlite3_errmsg()].
5271
** ^With the legacy interface, a more specific error code (for example,
5272
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
5273
** can be obtained by calling [sqlite3_reset()] on the
5274
** [prepared statement]. ^In the "v2" interface,
5275
** the more specific error code is returned directly by sqlite3_step().
5276
**
5277
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
5278
** Perhaps it was called on a [prepared statement] that has
5279
** already been [sqlite3_finalize | finalized] or on one that had
5280
** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
5281
** be the case that the same database connection is being used by two or
5282
** more threads at the same moment in time.
5283
**
5284
** For all versions of SQLite up to and including 3.6.23.1, a call to
5285
** [sqlite3_reset()] was required after sqlite3_step() returned anything
5286
** other than [SQLITE_ROW] before any subsequent invocation of
5287
** sqlite3_step(). Failure to reset the prepared statement using
5288
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
5289
** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1]),
5290
** sqlite3_step() began
5291
** calling [sqlite3_reset()] automatically in this circumstance rather
5292
** than returning [SQLITE_MISUSE]. This is not considered a compatibility
5293
** break because any application that ever receives an SQLITE_MISUSE error
5294
** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
5295
** can be used to restore the legacy behavior.
5296
**
5297
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
5298
** API always returns a generic error code, [SQLITE_ERROR], following any
5299
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
5300
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
5301
** specific [error codes] that better describes the error.
5302
** We admit that this is a goofy design. The problem has been fixed
5303
** with the "v2" interface. If you prepare all of your SQL statements
5304
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
5305
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
5306
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
5307
** then the more specific [error codes] are returned directly
5308
** by sqlite3_step(). The use of the "vX" interfaces is recommended.
5309
*/
5310
SQLITE_API int sqlite3_step(sqlite3_stmt*);
5311
5312
/*
5313
** CAPI3REF: Number of columns in a result set
5314
** METHOD: sqlite3_stmt
5315
**
5316
** ^The sqlite3_data_count(P) interface returns the number of columns in the
5317
** current row of the result set of [prepared statement] P.
5318
** ^If prepared statement P does not have results ready to return
5319
** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
5320
** interfaces) then sqlite3_data_count(P) returns 0.
5321
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
5322
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
5323
** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
5324
** will return non-zero if previous call to [sqlite3_step](P) returned
5325
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
5326
** where it always returns zero since each step of that multi-step
5327
** pragma returns 0 columns of data.
5328
**
5329
** See also: [sqlite3_column_count()]
5330
*/
5331
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
5332
5333
/*
5334
** CAPI3REF: Fundamental Datatypes
5335
** KEYWORDS: SQLITE_TEXT
5336
**
5337
** ^(Every value in SQLite has one of five fundamental datatypes:
5338
**
5339
** <ul>
5340
** <li> 64-bit signed integer
5341
** <li> 64-bit IEEE floating point number
5342
** <li> string
5343
** <li> BLOB
5344
** <li> NULL
5345
** </ul>)^
5346
**
5347
** These constants are codes for each of those types.
5348
**
5349
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
5350
** for a completely different meaning. Software that links against both
5351
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
5352
** SQLITE_TEXT.
5353
*/
5354
#define SQLITE_INTEGER 1
5355
#define SQLITE_FLOAT 2
5356
#define SQLITE_BLOB 4
5357
#define SQLITE_NULL 5
5358
#ifdef SQLITE_TEXT
5359
# undef SQLITE_TEXT
5360
#else
5361
# define SQLITE_TEXT 3
5362
#endif
5363
#define SQLITE3_TEXT 3
5364
5365
/*
5366
** CAPI3REF: Result Values From A Query
5367
** KEYWORDS: {column access functions}
5368
** METHOD: sqlite3_stmt
5369
**
5370
** <b>Summary:</b>
5371
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5372
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
5373
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
5374
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
5375
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
5376
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
5377
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
5378
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
5379
** [sqlite3_value|unprotected sqlite3_value] object.
5380
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5381
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
5382
** or a UTF-8 TEXT result in bytes
5383
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
5384
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5385
** TEXT in bytes
5386
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
5387
** datatype of the result
5388
** </table></blockquote>
5389
**
5390
** <b>Details:</b>
5391
**
5392
** ^These routines return information about a single column of the current
5393
** result row of a query. ^In every case the first argument is a pointer
5394
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
5395
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
5396
** and the second argument is the index of the column for which information
5397
** should be returned. ^The leftmost column of the result set has the index 0.
5398
** ^The number of columns in the result can be determined using
5399
** [sqlite3_column_count()].
5400
**
5401
** If the SQL statement does not currently point to a valid row, or if the
5402
** column index is out of range, the result is undefined.
5403
** These routines may only be called when the most recent call to
5404
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
5405
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
5406
** If any of these routines are called after [sqlite3_reset()] or
5407
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
5408
** something other than [SQLITE_ROW], the results are undefined.
5409
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
5410
** are called from a different thread while any of these routines
5411
** are pending, then the results are undefined.
5412
**
5413
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
5414
** each return the value of a result column in a specific data format. If
5415
** the result column is not initially in the requested format (for example,
5416
** if the query returns an integer but the sqlite3_column_text() interface
5417
** is used to extract the value) then an automatic type conversion is performed.
5418
**
5419
** ^The sqlite3_column_type() routine returns the
5420
** [SQLITE_INTEGER | datatype code] for the initial data type
5421
** of the result column. ^The returned value is one of [SQLITE_INTEGER],
5422
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
5423
** The return value of sqlite3_column_type() can be used to decide which
5424
** of the first six interface should be used to extract the column value.
5425
** The value returned by sqlite3_column_type() is only meaningful if no
5426
** automatic type conversions have occurred for the value in question.
5427
** After a type conversion, the result of calling sqlite3_column_type()
5428
** is undefined, though harmless. Future
5429
** versions of SQLite may change the behavior of sqlite3_column_type()
5430
** following a type conversion.
5431
**
5432
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
5433
** or sqlite3_column_bytes16() interfaces can be used to determine the size
5434
** of that BLOB or string.
5435
**
5436
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
5437
** routine returns the number of bytes in that BLOB or string.
5438
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
5439
** the string to UTF-8 and then returns the number of bytes.
5440
** ^If the result is a numeric value then sqlite3_column_bytes() uses
5441
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
5442
** the number of bytes in that string.
5443
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
5444
**
5445
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
5446
** routine returns the number of bytes in that BLOB or string.
5447
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
5448
** the string to UTF-16 and then returns the number of bytes.
5449
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
5450
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
5451
** the number of bytes in that string.
5452
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
5453
**
5454
** ^The values returned by [sqlite3_column_bytes()] and
5455
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
5456
** of the string. ^For clarity: the values returned by
5457
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
5458
** bytes in the string, not the number of characters.
5459
**
5460
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
5461
** even empty strings, are always zero-terminated. ^The return
5462
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
5463
**
5464
** ^Strings returned by sqlite3_column_text16() always have the endianness
5465
** which is native to the platform, regardless of the text encoding set
5466
** for the database.
5467
**
5468
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
5469
** [unprotected sqlite3_value] object. In a multithreaded environment,
5470
** an unprotected sqlite3_value object may only be used safely with
5471
** [sqlite3_bind_value()] and [sqlite3_result_value()].
5472
** If the [unprotected sqlite3_value] object returned by
5473
** [sqlite3_column_value()] is used in any other way, including calls
5474
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
5475
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
5476
** Hence, the sqlite3_column_value() interface
5477
** is normally only useful within the implementation of
5478
** [application-defined SQL functions] or [virtual tables], not within
5479
** top-level application code.
5480
**
5481
** These routines may attempt to convert the datatype of the result.
5482
** ^For example, if the internal representation is FLOAT and a text result
5483
** is requested, [sqlite3_snprintf()] is used internally to perform the
5484
** conversion automatically. ^(The following table details the conversions
5485
** that are applied:
5486
**
5487
** <blockquote>
5488
** <table border="1">
5489
** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
5490
**
5491
** <tr><td> NULL <td> INTEGER <td> Result is 0
5492
** <tr><td> NULL <td> FLOAT <td> Result is 0.0
5493
** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer
5494
** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer
5495
** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
5496
** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
5497
** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
5498
** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER
5499
** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
5500
** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB
5501
** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER
5502
** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL
5503
** <tr><td> TEXT <td> BLOB <td> No change
5504
** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER
5505
** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL
5506
** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator
5507
** </table>
5508
** </blockquote>)^
5509
**
5510
** Note that when type conversions occur, pointers returned by prior
5511
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5512
** sqlite3_column_text16() may be invalidated.
5513
** Type conversions and pointer invalidations might occur
5514
** in the following cases:
5515
**
5516
** <ul>
5517
** <li> The initial content is a BLOB and sqlite3_column_text() or
5518
** sqlite3_column_text16() is called. A zero-terminator might
5519
** need to be added to the string.</li>
5520
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5521
** sqlite3_column_text16() is called. The content must be converted
5522
** to UTF-16.</li>
5523
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5524
** sqlite3_column_text() is called. The content must be converted
5525
** to UTF-8.</li>
5526
** </ul>
5527
**
5528
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5529
** not invalidate a prior pointer, though of course the content of the buffer
5530
** that the prior pointer references will have been modified. Other kinds
5531
** of conversion are done in place when it is possible, but sometimes they
5532
** are not possible and in those cases prior pointers are invalidated.
5533
**
5534
** The safest policy is to invoke these routines
5535
** in one of the following ways:
5536
**
5537
** <ul>
5538
** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5539
** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5540
** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5541
** </ul>
5542
**
5543
** In other words, you should call sqlite3_column_text(),
5544
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5545
** into the desired format, then invoke sqlite3_column_bytes() or
5546
** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
5547
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5548
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5549
** with calls to sqlite3_column_bytes().
5550
**
5551
** ^The pointers returned are valid until a type conversion occurs as
5552
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5553
** [sqlite3_finalize()] is called. ^The memory space used to hold strings
5554
** and BLOBs is freed automatically. Do not pass the pointers returned
5555
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5556
** [sqlite3_free()].
5557
**
5558
** As long as the input parameters are correct, these routines will only
5559
** fail if an out-of-memory error occurs during a format conversion.
5560
** Only the following subset of interfaces are subject to out-of-memory
5561
** errors:
5562
**
5563
** <ul>
5564
** <li> sqlite3_column_blob()
5565
** <li> sqlite3_column_text()
5566
** <li> sqlite3_column_text16()
5567
** <li> sqlite3_column_bytes()
5568
** <li> sqlite3_column_bytes16()
5569
** </ul>
5570
**
5571
** If an out-of-memory error occurs, then the return value from these
5572
** routines is the same as if the column had contained an SQL NULL value.
5573
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5574
** by invoking the [sqlite3_errcode()] immediately after the suspect
5575
** return value is obtained and before any
5576
** other SQLite interface is called on the same [database connection].
5577
*/
5578
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5579
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5580
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5581
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5582
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5583
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5584
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5585
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5586
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5587
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5588
5589
/*
5590
** CAPI3REF: Destroy A Prepared Statement Object
5591
** DESTRUCTOR: sqlite3_stmt
5592
**
5593
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5594
** ^If the most recent evaluation of the statement encountered no errors
5595
** or if the statement has never been evaluated, then sqlite3_finalize() returns
5596
** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
5597
** sqlite3_finalize(S) returns the appropriate [error code] or
5598
** [extended error code].
5599
**
5600
** ^The sqlite3_finalize(S) routine can be called at any point during
5601
** the life cycle of [prepared statement] S:
5602
** before statement S is ever evaluated, after
5603
** one or more calls to [sqlite3_reset()], or after any call
5604
** to [sqlite3_step()] regardless of whether or not the statement has
5605
** completed execution.
5606
**
5607
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5608
**
5609
** The application must finalize every [prepared statement] in order to avoid
5610
** resource leaks. It is a grievous error for the application to try to use
5611
** a prepared statement after it has been finalized. Any use of a prepared
5612
** statement after it has been finalized can result in undefined and
5613
** undesirable behavior such as segfaults and heap corruption.
5614
*/
5615
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5616
5617
/*
5618
** CAPI3REF: Reset A Prepared Statement Object
5619
** METHOD: sqlite3_stmt
5620
**
5621
** The sqlite3_reset() function is called to reset a [prepared statement]
5622
** object back to its initial state, ready to be re-executed.
5623
** ^Any SQL statement variables that had values bound to them using
5624
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5625
** Use [sqlite3_clear_bindings()] to reset the bindings.
5626
**
5627
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5628
** back to the beginning of its program.
5629
**
5630
** ^The return code from [sqlite3_reset(S)] indicates whether or not
5631
** the previous evaluation of prepared statement S completed successfully.
5632
** ^If [sqlite3_step(S)] has never before been called on S or if
5633
** [sqlite3_step(S)] has not been called since the previous call
5634
** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return
5635
** [SQLITE_OK].
5636
**
5637
** ^If the most recent call to [sqlite3_step(S)] for the
5638
** [prepared statement] S indicated an error, then
5639
** [sqlite3_reset(S)] returns an appropriate [error code].
5640
** ^The [sqlite3_reset(S)] interface might also return an [error code]
5641
** if there were no prior errors but the process of resetting
5642
** the prepared statement caused a new error. ^For example, if an
5643
** [INSERT] statement with a [RETURNING] clause is only stepped one time,
5644
** that one call to [sqlite3_step(S)] might return SQLITE_ROW but
5645
** the overall statement might still fail and the [sqlite3_reset(S)] call
5646
** might return SQLITE_BUSY if locking constraints prevent the
5647
** database change from committing. Therefore, it is important that
5648
** applications check the return code from [sqlite3_reset(S)] even if
5649
** no prior call to [sqlite3_step(S)] indicated a problem.
5650
**
5651
** ^The [sqlite3_reset(S)] interface does not change the values
5652
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5653
*/
5654
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5655
5656
5657
/*
5658
** CAPI3REF: Create Or Redefine SQL Functions
5659
** KEYWORDS: {function creation routines}
5660
** METHOD: sqlite3
5661
**
5662
** ^These functions (collectively known as "function creation routines")
5663
** are used to add SQL functions or aggregates or to redefine the behavior
5664
** of existing SQL functions or aggregates. The only differences between
5665
** the three "sqlite3_create_function*" routines are the text encoding
5666
** expected for the second parameter (the name of the function being
5667
** created) and the presence or absence of a destructor callback for
5668
** the application data pointer. Function sqlite3_create_window_function()
5669
** is similar, but allows the user to supply the extra callback functions
5670
** needed by [aggregate window functions].
5671
**
5672
** ^The first parameter is the [database connection] to which the SQL
5673
** function is to be added. ^If an application uses more than one database
5674
** connection then application-defined SQL functions must be added
5675
** to each database connection separately.
5676
**
5677
** ^The second parameter is the name of the SQL function to be created or
5678
** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
5679
** representation, exclusive of the zero-terminator. ^Note that the name
5680
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5681
** ^Any attempt to create a function with a longer name
5682
** will result in [SQLITE_MISUSE] being returned.
5683
**
5684
** ^The third parameter (nArg)
5685
** is the number of arguments that the SQL function or
5686
** aggregate takes. ^If this parameter is -1, then the SQL function or
5687
** aggregate may take any number of arguments between 0 and the limit
5688
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
5689
** parameter is less than -1 or greater than 127 then the behavior is
5690
** undefined.
5691
**
5692
** ^The fourth parameter, eTextRep, specifies what
5693
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5694
** its parameters. The application should set this parameter to
5695
** [SQLITE_UTF16LE] if the function implementation invokes
5696
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5697
** implementation invokes [sqlite3_value_text16be()] on an input, or
5698
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5699
** otherwise. ^The same SQL function may be registered multiple times using
5700
** different preferred text encodings, with different implementations for
5701
** each encoding.
5702
** ^When multiple implementations of the same function are available, SQLite
5703
** will pick the one that involves the least amount of data conversion.
5704
**
5705
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5706
** to signal that the function will always return the same result given
5707
** the same inputs within a single SQL statement. Most SQL functions are
5708
** deterministic. The built-in [random()] SQL function is an example of a
5709
** function that is not deterministic. The SQLite query planner is able to
5710
** perform additional optimizations on deterministic functions, so use
5711
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
5712
**
5713
** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
5714
** flag, which if present prevents the function from being invoked from
5715
** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
5716
** index expressions, or the WHERE clause of partial indexes.
5717
**
5718
** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
5719
** all application-defined SQL functions that do not need to be
5720
** used inside of triggers, views, CHECK constraints, or other elements of
5721
** the database schema. This flag is especially recommended for SQL
5722
** functions that have side effects or reveal internal application state.
5723
** Without this flag, an attacker might be able to modify the schema of
5724
** a database file to include invocations of the function with parameters
5725
** chosen by the attacker, which the application will then execute when
5726
** the database file is opened and read.
5727
**
5728
** ^(The fifth parameter is an arbitrary pointer. The implementation of the
5729
** function can gain access to this pointer using [sqlite3_user_data()].)^
5730
**
5731
** ^The sixth, seventh and eighth parameters passed to the three
5732
** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
5733
** pointers to C-language functions that implement the SQL function or
5734
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5735
** callback only; NULL pointers must be passed as the xStep and xFinal
5736
** parameters. ^An aggregate SQL function requires an implementation of xStep
5737
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5738
** SQL function or aggregate, pass NULL pointers for all three function
5739
** callbacks.
5740
**
5741
** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
5742
** and xInverse) passed to sqlite3_create_window_function are pointers to
5743
** C-language callbacks that implement the new function. xStep and xFinal
5744
** must both be non-NULL. xValue and xInverse may either both be NULL, in
5745
** which case a regular aggregate function is created, or must both be
5746
** non-NULL, in which case the new function may be used as either an aggregate
5747
** or aggregate window function. More details regarding the implementation
5748
** of aggregate window functions are
5749
** [user-defined window functions|available here].
5750
**
5751
** ^(If the final parameter to sqlite3_create_function_v2() or
5752
** sqlite3_create_window_function() is not NULL, then it is the destructor for
5753
** the application data pointer. The destructor is invoked when the function
5754
** is deleted, either by being overloaded or when the database connection
5755
** closes.)^ ^The destructor is also invoked if the call to
5756
** sqlite3_create_function_v2() fails. ^When the destructor callback is
5757
** invoked, it is passed a single argument which is a copy of the application
5758
** data pointer which was the fifth parameter to sqlite3_create_function_v2().
5759
**
5760
** ^It is permitted to register multiple implementations of the same
5761
** functions with the same name but with either differing numbers of
5762
** arguments or differing preferred text encodings. ^SQLite will use
5763
** the implementation that most closely matches the way in which the
5764
** SQL function is used. ^A function implementation with a non-negative
5765
** nArg parameter is a better match than a function implementation with
5766
** a negative nArg. ^A function where the preferred text encoding
5767
** matches the database encoding is a better
5768
** match than a function where the encoding is different.
5769
** ^A function where the encoding difference is between UTF16le and UTF16be
5770
** is a closer match than a function where the encoding difference is
5771
** between UTF8 and UTF16.
5772
**
5773
** ^Built-in functions may be overloaded by new application-defined functions.
5774
**
5775
** ^An application-defined function is permitted to call other
5776
** SQLite interfaces. However, such calls must not
5777
** close the database connection nor finalize or reset the prepared
5778
** statement in which the function is running.
5779
*/
5780
SQLITE_API int sqlite3_create_function(
5781
sqlite3 *db,
5782
const char *zFunctionName,
5783
int nArg,
5784
int eTextRep,
5785
void *pApp,
5786
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5787
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5788
void (*xFinal)(sqlite3_context*)
5789
);
5790
SQLITE_API int sqlite3_create_function16(
5791
sqlite3 *db,
5792
const void *zFunctionName,
5793
int nArg,
5794
int eTextRep,
5795
void *pApp,
5796
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5797
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5798
void (*xFinal)(sqlite3_context*)
5799
);
5800
SQLITE_API int sqlite3_create_function_v2(
5801
sqlite3 *db,
5802
const char *zFunctionName,
5803
int nArg,
5804
int eTextRep,
5805
void *pApp,
5806
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5807
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5808
void (*xFinal)(sqlite3_context*),
5809
void(*xDestroy)(void*)
5810
);
5811
SQLITE_API int sqlite3_create_window_function(
5812
sqlite3 *db,
5813
const char *zFunctionName,
5814
int nArg,
5815
int eTextRep,
5816
void *pApp,
5817
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5818
void (*xFinal)(sqlite3_context*),
5819
void (*xValue)(sqlite3_context*),
5820
void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5821
void(*xDestroy)(void*)
5822
);
5823
5824
/*
5825
** CAPI3REF: Text Encodings
5826
**
5827
** These constants define integer codes that represent the various
5828
** text encodings supported by SQLite.
5829
**
5830
** <dl>
5831
** [[SQLITE_UTF8]] <dt>SQLITE_UTF8</dt><dd>Text is encoding as UTF-8</dd>
5832
**
5833
** [[SQLITE_UTF16LE]] <dt>SQLITE_UTF16LE</dt><dd>Text is encoding as UTF-16
5834
** with each code point being expressed "little endian" - the least significant
5835
** byte first. This is the usual encoding, for example on Windows.</dd>
5836
**
5837
** [[SQLITE_UTF16BE]] <dt>SQLITE_UTF16BE</dt><dd>Text is encoding as UTF-16
5838
** with each code point being expressed "big endian" - the most significant
5839
** byte first. This encoding is less common, but is still sometimes seen,
5840
** specially on older systems.
5841
**
5842
** [[SQLITE_UTF16]] <dt>SQLITE_UTF16</dt><dd>Text is encoding as UTF-16
5843
** with each code point being expressed either little endian or as big
5844
** endian, according to the native endianness of the host computer.
5845
**
5846
** [[SQLITE_ANY]] <dt>SQLITE_ANY</dt><dd>This encoding value may only be used
5847
** to declare the preferred text for [application-defined SQL functions]
5848
** created using [sqlite3_create_function()] and similar. If the preferred
5849
** encoding (the 4th parameter to sqlite3_create_function() - the eTextRep
5850
** parameter) is SQLITE_ANY, that indicates that the function does not have
5851
** a preference regarding the text encoding of its parameters and can take
5852
** any text encoding that the SQLite core find convenient to supply. This
5853
** option is deprecated. Please do not use it in new applications.
5854
**
5855
** [[SQLITE_UTF16_ALIGNED]] <dt>SQLITE_UTF16_ALIGNED</dt><dd>This encoding
5856
** value may be used as the 3rd parameter (the eTextRep parameter) to
5857
** [sqlite3_create_collation()] and similar. This encoding value means
5858
** that the application-defined collating sequence created expects its
5859
** input strings to be in UTF16 in native byte order, and that the start
5860
** of the strings must be aligned to a 2-byte boundary.
5861
**
5862
** [[SQLITE_UTF8_ZT]] <dt>SQLITE_UTF8_ZT</dt><dd>This option can only be
5863
** used to specify the text encoding to strings input to
5864
** [sqlite3_result_text64()] and [sqlite3_bind_text64()].
5865
** The SQLITE_UTF8_ZT encoding means that the input string (call it "z")
5866
** is UTF-8 encoded and that it is zero-terminated. If the length parameter
5867
** (call it "n") is non-negative, this encoding option means that the caller
5868
** guarantees that z array contains at least n+1 bytes and that the z&#91;n&#93;
5869
** byte has a value of zero.
5870
** This option gives the same output as SQLITE_UTF8, but can be more efficient
5871
** by avoiding the need to make a copy of the input string, in some cases.
5872
** However, if z is allocated to hold fewer than n+1 bytes or if the
5873
** z&#91;n&#93; byte is not zero, undefined behavior may result.
5874
** </dl>
5875
*/
5876
#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */
5877
#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */
5878
#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */
5879
#define SQLITE_UTF16 4 /* Use native byte order */
5880
#define SQLITE_ANY 5 /* Deprecated */
5881
#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
5882
#define SQLITE_UTF8_ZT 16 /* Zero-terminated UTF8 */
5883
5884
/*
5885
** CAPI3REF: Function Flags
5886
**
5887
** These constants may be ORed together with the
5888
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5889
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5890
** [sqlite3_create_function_v2()].
5891
**
5892
** <dl>
5893
** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
5894
** The SQLITE_DETERMINISTIC flag means that the new function always gives
5895
** the same output when the input parameters are the same.
5896
** The [abs|abs() function] is deterministic, for example, but
5897
** [randomblob|randomblob()] is not. Functions must
5898
** be deterministic in order to be used in certain contexts such as
5899
** with the WHERE clause of [partial indexes] or in [generated columns].
5900
** SQLite might also optimize deterministic functions by factoring them
5901
** out of inner loops.
5902
** </dd>
5903
**
5904
** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
5905
** The SQLITE_DIRECTONLY flag means that the function may only be invoked
5906
** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
5907
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5908
** [expression indexes], [partial indexes], or [generated columns].
5909
** <p>
5910
** The SQLITE_DIRECTONLY flag is recommended for any
5911
** [application-defined SQL function]
5912
** that has side-effects or that could potentially leak sensitive information.
5913
** This will prevent attacks in which an application is tricked
5914
** into using a database file that has had its schema surreptitiously
5915
** modified to invoke the application-defined function in ways that are
5916
** harmful.
5917
** <p>
5918
** Some people say it is good practice to set SQLITE_DIRECTONLY on all
5919
** [application-defined SQL functions], regardless of whether or not they
5920
** are security sensitive, as doing so prevents those functions from being used
5921
** inside of the database schema, and thus ensures that the database
5922
** can be inspected and modified using generic tools (such as the [CLI])
5923
** that do not have access to the application-defined functions.
5924
** </dd>
5925
**
5926
** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
5927
** The SQLITE_INNOCUOUS flag means that the function is unlikely
5928
** to cause problems even if misused. An innocuous function should have
5929
** no side effects and should not depend on any values other than its
5930
** input parameters. The [abs|abs() function] is an example of an
5931
** innocuous function.
5932
** The [load_extension() SQL function] is not innocuous because of its
5933
** side effects.
5934
** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
5935
** exactly the same. The [random|random() function] is an example of a
5936
** function that is innocuous but not deterministic.
5937
** <p>Some heightened security settings
5938
** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
5939
** disable the use of SQL functions inside views and triggers and in
5940
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5941
** [expression indexes], [partial indexes], and [generated columns] unless
5942
** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions
5943
** are innocuous. Developers are advised to avoid using the
5944
** SQLITE_INNOCUOUS flag for application-defined functions unless the
5945
** function has been carefully audited and found to be free of potentially
5946
** security-adverse side-effects and information-leaks.
5947
** </dd>
5948
**
5949
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
5950
** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
5951
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
5952
** This flag instructs SQLite to omit some corner-case optimizations that
5953
** might disrupt the operation of the [sqlite3_value_subtype()] function,
5954
** causing it to return zero rather than the correct subtype().
5955
** All SQL functions that invoke [sqlite3_value_subtype()] should have this
5956
** property. If the SQLITE_SUBTYPE property is omitted, then the return
5957
** value from [sqlite3_value_subtype()] might sometimes be zero even though
5958
** a non-zero subtype was specified by the function argument expression.
5959
**
5960
** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
5961
** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
5962
** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
5963
** result.
5964
** Every function that invokes [sqlite3_result_subtype()] should have this
5965
** property. If it does not, then the call to [sqlite3_result_subtype()]
5966
** might become a no-op if the function is used as a term in an
5967
** [expression index]. On the other hand, SQL functions that never invoke
5968
** [sqlite3_result_subtype()] should avoid setting this property, as the
5969
** purpose of this property is to disable certain optimizations that are
5970
** incompatible with subtypes.
5971
**
5972
** [[SQLITE_SELFORDER1]] <dt>SQLITE_SELFORDER1</dt><dd>
5973
** The SQLITE_SELFORDER1 flag indicates that the function is an aggregate
5974
** that internally orders the values provided to the first argument. The
5975
** ordered-set aggregate SQL notation with a single ORDER BY term can be
5976
** used to invoke this function. If the ordered-set aggregate notation is
5977
** used on a function that lacks this flag, then an error is raised. Note
5978
** that the ordered-set aggregate syntax is only available if SQLite is
5979
** built using the -DSQLITE_ENABLE_ORDERED_SET_AGGREGATES compile-time option.
5980
** </dd>
5981
** </dl>
5982
*/
5983
#define SQLITE_DETERMINISTIC 0x000000800
5984
#define SQLITE_DIRECTONLY 0x000080000
5985
#define SQLITE_SUBTYPE 0x000100000
5986
#define SQLITE_INNOCUOUS 0x000200000
5987
#define SQLITE_RESULT_SUBTYPE 0x001000000
5988
#define SQLITE_SELFORDER1 0x002000000
5989
5990
/*
5991
** CAPI3REF: Deprecated Functions
5992
** DEPRECATED
5993
**
5994
** These functions are [deprecated]. In order to maintain
5995
** backwards compatibility with older code, these functions continue
5996
** to be supported. However, new applications should avoid
5997
** the use of these functions. To encourage programmers to avoid
5998
** these functions, we will not explain what they do.
5999
*/
6000
#ifndef SQLITE_OMIT_DEPRECATED
6001
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
6002
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
6003
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
6004
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
6005
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
6006
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
6007
void*,sqlite3_int64);
6008
#endif
6009
6010
/*
6011
** CAPI3REF: Obtaining SQL Values
6012
** METHOD: sqlite3_value
6013
**
6014
** <b>Summary:</b>
6015
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
6016
** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
6017
** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
6018
** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
6019
** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
6020
** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
6021
** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
6022
** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
6023
** the native byteorder
6024
** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
6025
** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
6026
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
6027
** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
6028
** or a UTF-8 TEXT in bytes
6029
** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
6030
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
6031
** TEXT in bytes
6032
** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
6033
** datatype of the value
6034
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
6035
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
6036
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
6037
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
6038
** against a virtual table.
6039
** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
6040
** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
6041
** </table></blockquote>
6042
**
6043
** <b>Details:</b>
6044
**
6045
** These routines extract type, size, and content information from
6046
** [protected sqlite3_value] objects. Protected sqlite3_value objects
6047
** are used to pass parameter information into the functions that
6048
** implement [application-defined SQL functions] and [virtual tables].
6049
**
6050
** These routines work only with [protected sqlite3_value] objects.
6051
** Any attempt to use these routines on an [unprotected sqlite3_value]
6052
** is not threadsafe.
6053
**
6054
** ^These routines work just like the corresponding [column access functions]
6055
** except that these routines take a single [protected sqlite3_value] object
6056
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
6057
**
6058
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
6059
** in the native byte-order of the host machine. ^The
6060
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
6061
** extract UTF-16 strings as big-endian and little-endian respectively.
6062
**
6063
** ^If [sqlite3_value] object V was initialized
6064
** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
6065
** and if X and Y are strings that compare equal according to strcmp(X,Y),
6066
** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise,
6067
** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
6068
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
6069
**
6070
** ^(The sqlite3_value_type(V) interface returns the
6071
** [SQLITE_INTEGER | datatype code] for the initial datatype of the
6072
** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
6073
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
6074
** Other interfaces might change the datatype for an sqlite3_value object.
6075
** For example, if the datatype is initially SQLITE_INTEGER and
6076
** sqlite3_value_text(V) is called to extract a text value for that
6077
** integer, then subsequent calls to sqlite3_value_type(V) might return
6078
** SQLITE_TEXT. Whether or not a persistent internal datatype conversion
6079
** occurs is undefined and may change from one release of SQLite to the next.
6080
**
6081
** ^(The sqlite3_value_numeric_type() interface attempts to apply
6082
** numeric affinity to the value. This means that an attempt is
6083
** made to convert the value to an integer or floating point. If
6084
** such a conversion is possible without loss of information (in other
6085
** words, if the value is a string that looks like a number)
6086
** then the conversion is performed. Otherwise no conversion occurs.
6087
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
6088
**
6089
** ^Within the [xUpdate] method of a [virtual table], the
6090
** sqlite3_value_nochange(X) interface returns true if and only if
6091
** the column corresponding to X is unchanged by the UPDATE operation
6092
** that the xUpdate method call was invoked to implement and if
6093
** the prior [xColumn] method call that was invoked to extract
6094
** the value for that column returned without setting a result (probably
6095
** because it queried [sqlite3_vtab_nochange()] and found that the column
6096
** was unchanging). ^Within an [xUpdate] method, any value for which
6097
** sqlite3_value_nochange(X) is true will in all other respects appear
6098
** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other
6099
** than within an [xUpdate] method call for an UPDATE statement, then
6100
** the return value is arbitrary and meaningless.
6101
**
6102
** ^The sqlite3_value_frombind(X) interface returns non-zero if the
6103
** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
6104
** interfaces. ^If X comes from an SQL literal value, or a table column,
6105
** or an expression, then sqlite3_value_frombind(X) returns zero.
6106
**
6107
** Please pay particular attention to the fact that the pointer returned
6108
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
6109
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
6110
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
6111
** or [sqlite3_value_text16()].
6112
**
6113
** These routines must be called from the same thread as
6114
** the SQL function that supplied the [sqlite3_value*] parameters.
6115
**
6116
** As long as the input parameter is correct, these routines can only
6117
** fail if an out-of-memory error occurs while trying to do a
6118
** UTF8&rarr;UTF16 or UTF16&rarr;UTF8 conversion.
6119
** If an out-of-memory error occurs, then the return value from these
6120
** routines is the same as if the column had contained an SQL NULL value.
6121
** If the input sqlite3_value was not obtained from [sqlite3_value_dup()],
6122
** then valid SQL NULL returns can also be distinguished from
6123
** out-of-memory errors after extracting the value
6124
** by invoking the [sqlite3_errcode()] immediately after the suspicious
6125
** return value is obtained and before any
6126
** other SQLite interface is called on the same [database connection].
6127
** If the input sqlite3_value was obtained from sqlite3_value_dup() then
6128
** it is disconnected from the database connection and so sqlite3_errcode()
6129
** will not work.
6130
** In that case, the only way to distinguish an out-of-memory
6131
** condition from a true SQL NULL is to invoke sqlite3_value_type() on the
6132
** input to see if it is NULL prior to trying to extract the value.
6133
*/
6134
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
6135
SQLITE_API double sqlite3_value_double(sqlite3_value*);
6136
SQLITE_API int sqlite3_value_int(sqlite3_value*);
6137
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
6138
SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
6139
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
6140
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
6141
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
6142
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
6143
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
6144
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
6145
SQLITE_API int sqlite3_value_type(sqlite3_value*);
6146
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
6147
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
6148
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
6149
6150
/*
6151
** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
6152
** METHOD: sqlite3_value
6153
**
6154
** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
6155
** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
6156
** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X)
6157
** returns something other than SQLITE_TEXT, then the return value from
6158
** sqlite3_value_encoding(X) is meaningless. ^Calls to
6159
** [sqlite3_value_text(X)], [sqlite3_value_text16(X)],
6160
** [sqlite3_value_text16be(X)],
6161
** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
6162
** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
6163
** thus change the return from subsequent calls to sqlite3_value_encoding(X).
6164
**
6165
** This routine is intended for used by applications that test and validate
6166
** the SQLite implementation. This routine is inquiring about the opaque
6167
** internal state of an [sqlite3_value] object. Ordinary applications should
6168
** not need to know what the internal state of an sqlite3_value object is and
6169
** hence should not need to use this interface.
6170
*/
6171
SQLITE_API int sqlite3_value_encoding(sqlite3_value*);
6172
6173
/*
6174
** CAPI3REF: Finding The Subtype Of SQL Values
6175
** METHOD: sqlite3_value
6176
**
6177
** The sqlite3_value_subtype(V) function returns the subtype for
6178
** an [application-defined SQL function] argument V. The subtype
6179
** information can be used to pass a limited amount of context from
6180
** one SQL function to another. Use the [sqlite3_result_subtype()]
6181
** routine to set the subtype for the return value of an SQL function.
6182
**
6183
** Every [application-defined SQL function] that invokes this interface
6184
** should include the [SQLITE_SUBTYPE] property in the text
6185
** encoding argument when the function is [sqlite3_create_function|registered].
6186
** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
6187
** might return zero instead of the upstream subtype in some corner cases.
6188
*/
6189
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
6190
6191
/*
6192
** CAPI3REF: Copy And Free SQL Values
6193
** METHOD: sqlite3_value
6194
**
6195
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
6196
** object V and returns a pointer to that copy. ^The [sqlite3_value] returned
6197
** is a [protected sqlite3_value] object even if the input is not.
6198
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
6199
** memory allocation fails. ^If V is a [pointer value], then the result
6200
** of sqlite3_value_dup(V) is a NULL value.
6201
**
6202
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
6203
** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer
6204
** then sqlite3_value_free(V) is a harmless no-op.
6205
*/
6206
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
6207
SQLITE_API void sqlite3_value_free(sqlite3_value*);
6208
6209
/*
6210
** CAPI3REF: Obtain Aggregate Function Context
6211
** METHOD: sqlite3_context
6212
**
6213
** Implementations of aggregate SQL functions use this
6214
** routine to allocate memory for storing their state.
6215
**
6216
** ^The first time the sqlite3_aggregate_context(C,N) routine is called
6217
** for a particular aggregate function, SQLite allocates
6218
** N bytes of memory, zeroes out that memory, and returns a pointer
6219
** to the new memory. ^On second and subsequent calls to
6220
** sqlite3_aggregate_context() for the same aggregate function instance,
6221
** the same buffer is returned. Sqlite3_aggregate_context() is normally
6222
** called once for each invocation of the xStep callback and then one
6223
** last time when the xFinal callback is invoked. ^(When no rows match
6224
** an aggregate query, the xStep() callback of the aggregate function
6225
** implementation is never called and xFinal() is called exactly once.
6226
** In those cases, sqlite3_aggregate_context() might be called for the
6227
** first time from within xFinal().)^
6228
**
6229
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
6230
** when first called if N is less than or equal to zero or if a memory
6231
** allocation error occurs.
6232
**
6233
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
6234
** determined by the N parameter on the first successful call. Changing the
6235
** value of N in any subsequent call to sqlite3_aggregate_context() within
6236
** the same aggregate function instance will not resize the memory
6237
** allocation.)^ Within the xFinal callback, it is customary to set
6238
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
6239
** pointless memory allocations occur.
6240
**
6241
** ^SQLite automatically frees the memory allocated by
6242
** sqlite3_aggregate_context() when the aggregate query concludes.
6243
**
6244
** The first parameter must be a copy of the
6245
** [sqlite3_context | SQL function context] that is the first parameter
6246
** to the xStep or xFinal callback routine that implements the aggregate
6247
** function.
6248
**
6249
** This routine must be called from the same thread in which
6250
** the aggregate SQL function is running.
6251
*/
6252
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
6253
6254
/*
6255
** CAPI3REF: User Data For Functions
6256
** METHOD: sqlite3_context
6257
**
6258
** ^The sqlite3_user_data() interface returns a copy of
6259
** the pointer that was the pUserData parameter (the 5th parameter)
6260
** of the [sqlite3_create_function()]
6261
** and [sqlite3_create_function16()] routines that originally
6262
** registered the application defined function.
6263
**
6264
** This routine must be called from the same thread in which
6265
** the application-defined function is running.
6266
*/
6267
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
6268
6269
/*
6270
** CAPI3REF: Database Connection For Functions
6271
** METHOD: sqlite3_context
6272
**
6273
** ^The sqlite3_context_db_handle() interface returns a copy of
6274
** the pointer to the [database connection] (the 1st parameter)
6275
** of the [sqlite3_create_function()]
6276
** and [sqlite3_create_function16()] routines that originally
6277
** registered the application defined function.
6278
*/
6279
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
6280
6281
/*
6282
** CAPI3REF: Function Auxiliary Data
6283
** METHOD: sqlite3_context
6284
**
6285
** These functions may be used by (non-aggregate) SQL functions to
6286
** associate auxiliary data with argument values. If the same argument
6287
** value is passed to multiple invocations of the same SQL function during
6288
** query execution, under some circumstances the associated auxiliary data
6289
** might be preserved. An example of where this might be useful is in a
6290
** regular-expression matching function. The compiled version of the regular
6291
** expression can be stored as auxiliary data associated with the pattern
6292
** string. Then as long as the pattern string remains the same,
6293
** the compiled regular expression can be reused on multiple
6294
** invocations of the same function.
6295
**
6296
** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary
6297
** data associated by the sqlite3_set_auxdata(C,N,P,X) function with the
6298
** Nth argument value to the application-defined function. ^N is zero
6299
** for the left-most function argument. ^If there is no auxiliary data
6300
** associated with the function argument, the sqlite3_get_auxdata(C,N)
6301
** interface returns a NULL pointer.
6302
**
6303
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the
6304
** N-th argument of the application-defined function. ^Subsequent
6305
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
6306
** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or
6307
** NULL if the auxiliary data has been discarded.
6308
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
6309
** SQLite will invoke the destructor function X with parameter P exactly
6310
** once, when the auxiliary data is discarded.
6311
** SQLite is free to discard the auxiliary data at any time, including: <ul>
6312
** <li> ^(when the corresponding function parameter changes)^, or
6313
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
6314
** SQL statement)^, or
6315
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
6316
** parameter)^, or
6317
** <li> ^(during the original sqlite3_set_auxdata() call when a memory
6318
** allocation error occurs.)^
6319
** <li> ^(during the original sqlite3_set_auxdata() call if the function
6320
** is evaluated during query planning instead of during query execution,
6321
** as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul>
6322
**
6323
** Note the last two bullets in particular. The destructor X in
6324
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
6325
** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()
6326
** should be called near the end of the function implementation and the
6327
** function implementation should not make any use of P after
6328
** sqlite3_set_auxdata() has been called. Furthermore, a call to
6329
** sqlite3_get_auxdata() that occurs immediately after a corresponding call
6330
** to sqlite3_set_auxdata() might still return NULL if an out-of-memory
6331
** condition occurred during the sqlite3_set_auxdata() call or if the
6332
** function is being evaluated during query planning rather than during
6333
** query execution.
6334
**
6335
** ^(In practice, auxiliary data is preserved between function calls for
6336
** function parameters that are compile-time constants, including literal
6337
** values and [parameters] and expressions composed from the same.)^
6338
**
6339
** The value of the N parameter to these interfaces should be non-negative.
6340
** Future enhancements may make use of negative N values to define new
6341
** kinds of function caching behavior.
6342
**
6343
** These routines must be called from the same thread in which
6344
** the SQL function is running.
6345
**
6346
** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()].
6347
*/
6348
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
6349
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
6350
6351
/*
6352
** CAPI3REF: Database Connection Client Data
6353
** METHOD: sqlite3
6354
**
6355
** These functions are used to associate one or more named pointers
6356
** with a [database connection].
6357
** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P
6358
** to be attached to [database connection] D using name N. Subsequent
6359
** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P
6360
** or a NULL pointer if there were no prior calls to
6361
** sqlite3_set_clientdata() with the same values of D and N.
6362
** Names are compared using strcmp() and are thus case sensitive.
6363
** It returns 0 on success and SQLITE_NOMEM on allocation failure.
6364
**
6365
** If P and X are both non-NULL, then the destructor X is invoked with
6366
** argument P on the first of the following occurrences:
6367
** <ul>
6368
** <li> An out-of-memory error occurs during the call to
6369
** sqlite3_set_clientdata() which attempts to register pointer P.
6370
** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made
6371
** with the same D and N parameters.
6372
** <li> The database connection closes. SQLite does not make any guarantees
6373
** about the order in which destructors are called, only that all
6374
** destructors will be called exactly once at some point during the
6375
** database connection closing process.
6376
** </ul>
6377
**
6378
** SQLite does not do anything with client data other than invoke
6379
** destructors on the client data at the appropriate time. The intended
6380
** use for client data is to provide a mechanism for wrapper libraries
6381
** to store additional information about an SQLite database connection.
6382
**
6383
** There is no limit (other than available memory) on the number of different
6384
** client data pointers (with different names) that can be attached to a
6385
** single database connection. However, the current implementation stores
6386
** the content on a linked list. Insert and retrieval performance will
6387
** be proportional to the number of entries. The design use case, and
6388
** the use case for which the implementation is optimized, is
6389
** that an application will store only small number of client data names,
6390
** typically just one or two. This interface is not intended to be a
6391
** generalized key/value store for thousands or millions of keys. It
6392
** will work for that, but performance might be disappointing.
6393
**
6394
** There is no way to enumerate the client data pointers
6395
** associated with a database connection. The N parameter can be thought
6396
** of as a secret key such that only code that knows the secret key is able
6397
** to access the associated data.
6398
**
6399
** Security Warning: These interfaces should not be exposed in scripting
6400
** languages or in other circumstances where it might be possible for an
6401
** attacker to invoke them. Any agent that can invoke these interfaces
6402
** can probably also take control of the process.
6403
**
6404
** Database connection client data is only available for SQLite
6405
** version 3.44.0 ([dateof:3.44.0]) and later.
6406
**
6407
** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()].
6408
*/
6409
SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*);
6410
SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*));
6411
6412
/*
6413
** CAPI3REF: Constants Defining Special Destructor Behavior
6414
**
6415
** These are special values for the destructor that is passed in as the
6416
** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
6417
** argument is SQLITE_STATIC, it means that the content pointer is constant
6418
** and will never change. It does not need to be destroyed. ^The
6419
** SQLITE_TRANSIENT value means that the content will likely change in
6420
** the near future and that SQLite should make its own private copy of
6421
** the content before returning.
6422
**
6423
** The typedef is necessary to work around problems in certain
6424
** C++ compilers.
6425
*/
6426
typedef void (*sqlite3_destructor_type)(void*);
6427
#define SQLITE_STATIC ((sqlite3_destructor_type)0)
6428
#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
6429
6430
/*
6431
** CAPI3REF: Setting The Result Of An SQL Function
6432
** METHOD: sqlite3_context
6433
**
6434
** These routines are used by the xFunc or xFinal callbacks that
6435
** implement SQL functions and aggregates. See
6436
** [sqlite3_create_function()] and [sqlite3_create_function16()]
6437
** for additional information.
6438
**
6439
** These functions work very much like the [parameter binding] family of
6440
** functions used to bind values to host parameters in prepared statements.
6441
** Refer to the [SQL parameter] documentation for additional information.
6442
**
6443
** ^The sqlite3_result_blob() interface sets the result from
6444
** an application-defined function to be the BLOB whose content is pointed
6445
** to by the second parameter and which is N bytes long where N is the
6446
** third parameter.
6447
**
6448
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
6449
** interfaces set the result of the application-defined function to be
6450
** a BLOB containing all zero bytes and N bytes in size.
6451
**
6452
** ^The sqlite3_result_double() interface sets the result from
6453
** an application-defined function to be a floating point value specified
6454
** by its 2nd argument.
6455
**
6456
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
6457
** cause the implemented SQL function to throw an exception.
6458
** ^SQLite uses the string pointed to by the
6459
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
6460
** as the text of an error message. ^SQLite interprets the error
6461
** message string from sqlite3_result_error() as UTF-8. ^SQLite
6462
** interprets the string from sqlite3_result_error16() as UTF-16 using
6463
** the same [byte-order determination rules] as [sqlite3_bind_text16()].
6464
** ^If the third parameter to sqlite3_result_error()
6465
** or sqlite3_result_error16() is negative then SQLite takes as the error
6466
** message all text up through the first zero character.
6467
** ^If the third parameter to sqlite3_result_error() or
6468
** sqlite3_result_error16() is non-negative then SQLite takes that many
6469
** bytes (not characters) from the 2nd parameter as the error message.
6470
** ^The sqlite3_result_error() and sqlite3_result_error16()
6471
** routines make a private copy of the error message text before
6472
** they return. Hence, the calling function can deallocate or
6473
** modify the text after they return without harm.
6474
** ^The sqlite3_result_error_code() function changes the error code
6475
** returned by SQLite as a result of an error in a function. ^By default,
6476
** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
6477
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
6478
**
6479
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
6480
** error indicating that a string or BLOB is too long to represent.
6481
**
6482
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
6483
** error indicating that a memory allocation failed.
6484
**
6485
** ^The sqlite3_result_int() interface sets the return value
6486
** of the application-defined function to be the 32-bit signed integer
6487
** value given in the 2nd argument.
6488
** ^The sqlite3_result_int64() interface sets the return value
6489
** of the application-defined function to be the 64-bit signed integer
6490
** value given in the 2nd argument.
6491
**
6492
** ^The sqlite3_result_null() interface sets the return value
6493
** of the application-defined function to be NULL.
6494
**
6495
** ^The sqlite3_result_text(), sqlite3_result_text16(),
6496
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
6497
** set the return value of the application-defined function to be
6498
** a text string which is represented as UTF-8, UTF-16 native byte order,
6499
** UTF-16 little endian, or UTF-16 big endian, respectively.
6500
** ^The sqlite3_result_text64(C,Z,N,D,E) interface sets the return value of an
6501
** application-defined function to be a text string in an encoding
6502
** specified the E parameter, which must be one
6503
** of [SQLITE_UTF8], [SQLITE_UTF8_ZT], [SQLITE_UTF16], [SQLITE_UTF16BE],
6504
** or [SQLITE_UTF16LE]. ^The special value [SQLITE_UTF8_ZT] means that
6505
** the result text is both UTF-8 and zero-terminated. In other words,
6506
** SQLITE_UTF8_ZT means that the Z array holds at least N+1 bytes and that
6507
** the Z&#91;N&#93; is zero.
6508
** ^SQLite takes the text result from the application from
6509
** the 2nd parameter of the sqlite3_result_text* interfaces.
6510
** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
6511
** other than sqlite3_result_text64() is negative, then SQLite computes
6512
** the string length itself by searching the 2nd parameter for the first
6513
** zero character.
6514
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
6515
** is non-negative, then as many bytes (not characters) of the text
6516
** pointed to by the 2nd parameter are taken as the application-defined
6517
** function result. If the 3rd parameter is non-negative, then it
6518
** must be the byte offset into the string where the NUL terminator would
6519
** appear if the string were NUL terminated. If any NUL characters occur
6520
** in the string at a byte offset that is less than the value of the 3rd
6521
** parameter, then the resulting string will contain embedded NULs and the
6522
** result of expressions operating on strings with embedded NULs is undefined.
6523
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6524
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
6525
** function as the destructor on the text or BLOB result when it has
6526
** finished using that result.
6527
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
6528
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
6529
** assumes that the text or BLOB result is in constant space and does not
6530
** copy the content of the parameter nor call a destructor on the content
6531
** when it has finished using that result.
6532
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6533
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
6534
** then SQLite makes a copy of the result into space obtained
6535
** from [sqlite3_malloc()] before it returns.
6536
**
6537
** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
6538
** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
6539
** when the encoding is not UTF8, if the input UTF16 begins with a
6540
** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
6541
** string and the rest of the string is interpreted according to the
6542
** byte-order specified by the BOM. ^The byte-order specified by
6543
** the BOM at the beginning of the text overrides the byte-order
6544
** specified by the interface procedure. ^So, for example, if
6545
** sqlite3_result_text16le() is invoked with text that begins
6546
** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
6547
** first two bytes of input are skipped and the remaining input
6548
** is interpreted as UTF16BE text.
6549
**
6550
** ^For UTF16 input text to the sqlite3_result_text16(),
6551
** sqlite3_result_text16be(), sqlite3_result_text16le(), and
6552
** sqlite3_result_text64() routines, if the text contains invalid
6553
** UTF16 characters, the invalid characters might be converted
6554
** into the unicode replacement character, U+FFFD.
6555
**
6556
** ^The sqlite3_result_value() interface sets the result of
6557
** the application-defined function to be a copy of the
6558
** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
6559
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
6560
** so that the [sqlite3_value] specified in the parameter may change or
6561
** be deallocated after sqlite3_result_value() returns without harm.
6562
** ^A [protected sqlite3_value] object may always be used where an
6563
** [unprotected sqlite3_value] object is required, so either
6564
** kind of [sqlite3_value] object can be used with this interface.
6565
**
6566
** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
6567
** SQL NULL value, just like [sqlite3_result_null(C)], except that it
6568
** also associates the host-language pointer P or type T with that
6569
** NULL value such that the pointer can be retrieved within an
6570
** [application-defined SQL function] using [sqlite3_value_pointer()].
6571
** ^If the D parameter is not NULL, then it is a pointer to a destructor
6572
** for the P parameter. ^SQLite invokes D with P as its only argument
6573
** when SQLite is finished with P. The T parameter should be a static
6574
** string and preferably a string literal. The sqlite3_result_pointer()
6575
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
6576
**
6577
** If these routines are called from within a different thread
6578
** than the one containing the application-defined function that received
6579
** the [sqlite3_context] pointer, the results are undefined.
6580
*/
6581
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
6582
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
6583
sqlite3_uint64,void(*)(void*));
6584
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
6585
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
6586
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
6587
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
6588
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
6589
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
6590
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
6591
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
6592
SQLITE_API void sqlite3_result_null(sqlite3_context*);
6593
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
6594
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char *z, sqlite3_uint64 n,
6595
void(*)(void*), unsigned char encoding);
6596
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
6597
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
6598
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
6599
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
6600
SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
6601
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
6602
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
6603
6604
6605
/*
6606
** CAPI3REF: Setting The Subtype Of An SQL Function
6607
** METHOD: sqlite3_context
6608
**
6609
** The sqlite3_result_subtype(C,T) function causes the subtype of
6610
** the result from the [application-defined SQL function] with
6611
** [sqlite3_context] C to be the value T. Only the lower 8 bits
6612
** of the subtype T are preserved in current versions of SQLite;
6613
** higher order bits are discarded.
6614
** The number of subtype bytes preserved by SQLite might increase
6615
** in future releases of SQLite.
6616
**
6617
** Every [application-defined SQL function] that invokes this interface
6618
** should include the [SQLITE_RESULT_SUBTYPE] property in its
6619
** text encoding argument when the SQL function is
6620
** [sqlite3_create_function|registered]. If the [SQLITE_RESULT_SUBTYPE]
6621
** property is omitted from the function that invokes sqlite3_result_subtype(),
6622
** then in some cases the sqlite3_result_subtype() might fail to set
6623
** the result subtype.
6624
**
6625
** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
6626
** SQL function that invokes the sqlite3_result_subtype() interface
6627
** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
6628
** an error. Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
6629
** by default.
6630
*/
6631
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
6632
6633
/*
6634
** CAPI3REF: Define New Collating Sequences
6635
** METHOD: sqlite3
6636
**
6637
** ^These functions add, remove, or modify a [collation] associated
6638
** with the [database connection] specified as the first argument.
6639
**
6640
** ^The name of the collation is a UTF-8 string
6641
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
6642
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
6643
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
6644
** considered to be the same name.
6645
**
6646
** ^(The third argument (eTextRep) must be one of the constants:
6647
** <ul>
6648
** <li> [SQLITE_UTF8],
6649
** <li> [SQLITE_UTF16LE],
6650
** <li> [SQLITE_UTF16BE],
6651
** <li> [SQLITE_UTF16], or
6652
** <li> [SQLITE_UTF16_ALIGNED].
6653
** </ul>)^
6654
** ^The eTextRep argument determines the encoding of strings passed
6655
** to the collating function callback, xCompare.
6656
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
6657
** force strings to be UTF16 with native byte order.
6658
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
6659
** on an even byte address.
6660
**
6661
** ^The fourth argument, pArg, is an application data pointer that is passed
6662
** through as the first argument to the collating function callback.
6663
**
6664
** ^The fifth argument, xCompare, is a pointer to the collating function.
6665
** ^Multiple collating functions can be registered using the same name but
6666
** with different eTextRep parameters and SQLite will use whichever
6667
** function requires the least amount of data transformation.
6668
** ^If the xCompare argument is NULL then the collating function is
6669
** deleted. ^When all collating functions having the same name are deleted,
6670
** that collation is no longer usable.
6671
**
6672
** ^The collating function callback is invoked with a copy of the pArg
6673
** application data pointer and with two strings in the encoding specified
6674
** by the eTextRep argument. The two integer parameters to the collating
6675
** function callback are the length of the two strings, in bytes. The collating
6676
** function must return an integer that is negative, zero, or positive
6677
** if the first string is less than, equal to, or greater than the second,
6678
** respectively. A collating function must always return the same answer
6679
** given the same inputs. If two or more collating functions are registered
6680
** to the same collation name (using different eTextRep values) then all
6681
** must give an equivalent answer when invoked with equivalent strings.
6682
** The collating function must obey the following properties for all
6683
** strings A, B, and C:
6684
**
6685
** <ol>
6686
** <li> If A==B then B==A.
6687
** <li> If A==B and B==C then A==C.
6688
** <li> If A&lt;B THEN B&gt;A.
6689
** <li> If A&lt;B and B&lt;C then A&lt;C.
6690
** </ol>
6691
**
6692
** If a collating function fails any of the above constraints and that
6693
** collating function is registered and used, then the behavior of SQLite
6694
** is undefined.
6695
**
6696
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
6697
** with the addition that the xDestroy callback is invoked on pArg when
6698
** the collating function is deleted.
6699
** ^Collating functions are deleted when they are overridden by later
6700
** calls to the collation creation functions or when the
6701
** [database connection] is closed using [sqlite3_close()].
6702
**
6703
** ^The xDestroy callback is <u>not</u> called if the
6704
** sqlite3_create_collation_v2() function fails. Applications that invoke
6705
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
6706
** check the return code and dispose of the application data pointer
6707
** themselves rather than expecting SQLite to deal with it for them.
6708
** This is different from every other SQLite interface. The inconsistency
6709
** is unfortunate but cannot be changed without breaking backwards
6710
** compatibility.
6711
**
6712
** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
6713
*/
6714
SQLITE_API int sqlite3_create_collation(
6715
sqlite3*,
6716
const char *zName,
6717
int eTextRep,
6718
void *pArg,
6719
int(*xCompare)(void*,int,const void*,int,const void*)
6720
);
6721
SQLITE_API int sqlite3_create_collation_v2(
6722
sqlite3*,
6723
const char *zName,
6724
int eTextRep,
6725
void *pArg,
6726
int(*xCompare)(void*,int,const void*,int,const void*),
6727
void(*xDestroy)(void*)
6728
);
6729
SQLITE_API int sqlite3_create_collation16(
6730
sqlite3*,
6731
const void *zName,
6732
int eTextRep,
6733
void *pArg,
6734
int(*xCompare)(void*,int,const void*,int,const void*)
6735
);
6736
6737
/*
6738
** CAPI3REF: Collation Needed Callbacks
6739
** METHOD: sqlite3
6740
**
6741
** ^To avoid having to register all collation sequences before a database
6742
** can be used, a single callback function may be registered with the
6743
** [database connection] to be invoked whenever an undefined collation
6744
** sequence is required.
6745
**
6746
** ^If the function is registered using the sqlite3_collation_needed() API,
6747
** then it is passed the names of undefined collation sequences as strings
6748
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
6749
** the names are passed as UTF-16 in machine native byte order.
6750
** ^A call to either function replaces the existing collation-needed callback.
6751
**
6752
** ^(When the callback is invoked, the first argument passed is a copy
6753
** of the second argument to sqlite3_collation_needed() or
6754
** sqlite3_collation_needed16(). The second argument is the database
6755
** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
6756
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
6757
** sequence function required. The fourth parameter is the name of the
6758
** required collation sequence.)^
6759
**
6760
** The callback function should register the desired collation using
6761
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
6762
** [sqlite3_create_collation_v2()].
6763
*/
6764
SQLITE_API int sqlite3_collation_needed(
6765
sqlite3*,
6766
void*,
6767
void(*)(void*,sqlite3*,int eTextRep,const char*)
6768
);
6769
SQLITE_API int sqlite3_collation_needed16(
6770
sqlite3*,
6771
void*,
6772
void(*)(void*,sqlite3*,int eTextRep,const void*)
6773
);
6774
6775
#ifdef SQLITE_ENABLE_CEROD
6776
/*
6777
** Specify the activation key for a CEROD database. Unless
6778
** activated, none of the CEROD routines will work.
6779
*/
6780
SQLITE_API void sqlite3_activate_cerod(
6781
const char *zPassPhrase /* Activation phrase */
6782
);
6783
#endif
6784
6785
/*
6786
** CAPI3REF: Suspend Execution For A Short Time
6787
**
6788
** The sqlite3_sleep() function causes the current thread to suspend execution
6789
** for at least a number of milliseconds specified in its parameter.
6790
**
6791
** If the operating system does not support sleep requests with
6792
** millisecond time resolution, then the time will be rounded up to
6793
** the nearest second. The number of milliseconds of sleep actually
6794
** requested from the operating system is returned.
6795
**
6796
** ^SQLite implements this interface by calling the xSleep()
6797
** method of the default [sqlite3_vfs] object. If the xSleep() method
6798
** of the default VFS is not implemented correctly, or not implemented at
6799
** all, then the behavior of sqlite3_sleep() may deviate from the description
6800
** in the previous paragraphs.
6801
**
6802
** If a negative argument is passed to sqlite3_sleep() the results vary by
6803
** VFS and operating system. Some system treat a negative argument as an
6804
** instruction to sleep forever. Others understand it to mean do not sleep
6805
** at all. ^In SQLite version 3.42.0 and later, a negative
6806
** argument passed into sqlite3_sleep() is changed to zero before it is relayed
6807
** down into the xSleep method of the VFS.
6808
*/
6809
SQLITE_API int sqlite3_sleep(int);
6810
6811
/*
6812
** CAPI3REF: Name Of The Folder Holding Temporary Files
6813
**
6814
** ^(If this global variable is made to point to a string which is
6815
** the name of a folder (a.k.a. directory), then all temporary files
6816
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
6817
** will be placed in that directory.)^ ^If this variable
6818
** is a NULL pointer, then SQLite performs a search for an appropriate
6819
** temporary file directory.
6820
**
6821
** Applications are strongly discouraged from using this global variable.
6822
** It is required to set a temporary folder on Windows Runtime (WinRT).
6823
** But for all other platforms, it is highly recommended that applications
6824
** neither read nor write this variable. This global variable is a relic
6825
** that exists for backwards compatibility of legacy applications and should
6826
** be avoided in new projects.
6827
**
6828
** It is not safe to read or modify this variable in more than one
6829
** thread at a time. It is not safe to read or modify this variable
6830
** if a [database connection] is being used at the same time in a separate
6831
** thread.
6832
** It is intended that this variable be set once
6833
** as part of process initialization and before any SQLite interface
6834
** routines have been called and that this variable remain unchanged
6835
** thereafter.
6836
**
6837
** ^The [temp_store_directory pragma] may modify this variable and cause
6838
** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6839
** the [temp_store_directory pragma] always assumes that any string
6840
** that this variable points to is held in memory obtained from
6841
** [sqlite3_malloc] and the pragma may attempt to free that memory
6842
** using [sqlite3_free].
6843
** Hence, if this variable is modified directly, either it should be
6844
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6845
** or else the use of the [temp_store_directory pragma] should be avoided.
6846
** Except when requested by the [temp_store_directory pragma], SQLite
6847
** does not free the memory that sqlite3_temp_directory points to. If
6848
** the application wants that memory to be freed, it must do
6849
** so itself, taking care to only do so after all [database connection]
6850
** objects have been destroyed.
6851
**
6852
** <b>Note to Windows Runtime users:</b> The temporary directory must be set
6853
** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various
6854
** features that require the use of temporary files may fail. Here is an
6855
** example of how to do this using C++ with the Windows Runtime:
6856
**
6857
** <blockquote><pre>
6858
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6859
** &nbsp; TemporaryFolder->Path->Data();
6860
** char zPathBuf&#91;MAX_PATH + 1&#93;;
6861
** memset(zPathBuf, 0, sizeof(zPathBuf));
6862
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6863
** &nbsp; NULL, NULL);
6864
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6865
** </pre></blockquote>
6866
*/
6867
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
6868
6869
/*
6870
** CAPI3REF: Name Of The Folder Holding Database Files
6871
**
6872
** ^(If this global variable is made to point to a string which is
6873
** the name of a folder (a.k.a. directory), then all database files
6874
** specified with a relative pathname and created or accessed by
6875
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6876
** to be relative to that directory.)^ ^If this variable is a NULL
6877
** pointer, then SQLite assumes that all database files specified
6878
** with a relative pathname are relative to the current directory
6879
** for the process. Only the windows VFS makes use of this global
6880
** variable; it is ignored by the unix VFS.
6881
**
6882
** Changing the value of this variable while a database connection is
6883
** open can result in a corrupt database.
6884
**
6885
** It is not safe to read or modify this variable in more than one
6886
** thread at a time. It is not safe to read or modify this variable
6887
** if a [database connection] is being used at the same time in a separate
6888
** thread.
6889
** It is intended that this variable be set once
6890
** as part of process initialization and before any SQLite interface
6891
** routines have been called and that this variable remain unchanged
6892
** thereafter.
6893
**
6894
** ^The [data_store_directory pragma] may modify this variable and cause
6895
** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
6896
** the [data_store_directory pragma] always assumes that any string
6897
** that this variable points to is held in memory obtained from
6898
** [sqlite3_malloc] and the pragma may attempt to free that memory
6899
** using [sqlite3_free].
6900
** Hence, if this variable is modified directly, either it should be
6901
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6902
** or else the use of the [data_store_directory pragma] should be avoided.
6903
*/
6904
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
6905
6906
/*
6907
** CAPI3REF: Win32 Specific Interface
6908
**
6909
** These interfaces are available only on Windows. The
6910
** [sqlite3_win32_set_directory] interface is used to set the value associated
6911
** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6912
** zValue, depending on the value of the type parameter. The zValue parameter
6913
** should be NULL to cause the previous value to be freed via [sqlite3_free];
6914
** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6915
** prior to being used. The [sqlite3_win32_set_directory] interface returns
6916
** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6917
** or [SQLITE_NOMEM] if memory could not be allocated. The value of the
6918
** [sqlite3_data_directory] variable is intended to act as a replacement for
6919
** the current directory on the sub-platforms of Win32 where that concept is
6920
** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and
6921
** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6922
** sqlite3_win32_set_directory interface except the string parameter must be
6923
** UTF-8 or UTF-16, respectively.
6924
*/
6925
SQLITE_API int sqlite3_win32_set_directory(
6926
unsigned long type, /* Identifier for directory being set or reset */
6927
void *zValue /* New value for directory being set or reset */
6928
);
6929
SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6930
SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6931
6932
/*
6933
** CAPI3REF: Win32 Directory Types
6934
**
6935
** These macros are only available on Windows. They define the allowed values
6936
** for the type argument to the [sqlite3_win32_set_directory] interface.
6937
*/
6938
#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1
6939
#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2
6940
6941
/*
6942
** CAPI3REF: Test For Auto-Commit Mode
6943
** KEYWORDS: {autocommit mode}
6944
** METHOD: sqlite3
6945
**
6946
** ^The sqlite3_get_autocommit() interface returns non-zero or
6947
** zero if the given database connection is or is not in autocommit mode,
6948
** respectively. ^Autocommit mode is on by default.
6949
** ^Autocommit mode is disabled by a [BEGIN] statement.
6950
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6951
**
6952
** If certain kinds of errors occur on a statement within a multi-statement
6953
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6954
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6955
** transaction might be rolled back automatically. The only way to
6956
** find out whether SQLite automatically rolled back the transaction after
6957
** an error is to use this function.
6958
**
6959
** If another thread changes the autocommit status of the database
6960
** connection while this routine is running, then the return value
6961
** is undefined.
6962
*/
6963
SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6964
6965
/*
6966
** CAPI3REF: Find The Database Handle Of A Prepared Statement
6967
** METHOD: sqlite3_stmt
6968
**
6969
** ^The sqlite3_db_handle interface returns the [database connection] handle
6970
** to which a [prepared statement] belongs. ^The [database connection]
6971
** returned by sqlite3_db_handle is the same [database connection]
6972
** that was the first argument
6973
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6974
** create the statement in the first place.
6975
*/
6976
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6977
6978
/*
6979
** CAPI3REF: Return The Schema Name For A Database Connection
6980
** METHOD: sqlite3
6981
**
6982
** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
6983
** for the N-th database on database connection D, or a NULL pointer if N is
6984
** out of range. An N value of 0 means the main database file. An N of 1 is
6985
** the "temp" schema. Larger values of N correspond to various ATTACH-ed
6986
** databases.
6987
**
6988
** Space to hold the string that is returned by sqlite3_db_name() is managed
6989
** by SQLite itself. The string might be deallocated by any operation that
6990
** changes the schema, including [ATTACH] or [DETACH] or calls to
6991
** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
6992
** occur on a different thread. Applications that need to
6993
** remember the string long-term should make their own copy. Applications that
6994
** are accessing the same database connection simultaneously on multiple
6995
** threads should mutex-protect calls to this API and should make their own
6996
** private copy of the result prior to releasing the mutex.
6997
*/
6998
SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
6999
7000
/*
7001
** CAPI3REF: Return The Filename For A Database Connection
7002
** METHOD: sqlite3
7003
**
7004
** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
7005
** associated with database N of connection D.
7006
** ^If there is no attached database N on the database
7007
** connection D, or if database N is a temporary or in-memory database, then
7008
** this function will return either a NULL pointer or an empty string.
7009
**
7010
** ^The string value returned by this routine is owned and managed by
7011
** the database connection. ^The value will be valid until the database N
7012
** is [DETACH]-ed or until the database connection closes.
7013
**
7014
** ^The filename returned by this function is the output of the
7015
** xFullPathname method of the [VFS]. ^In other words, the filename
7016
** will be an absolute pathname, even if the filename used
7017
** to open the database originally was a URI or relative pathname.
7018
**
7019
** If the filename pointer returned by this routine is not NULL, then it
7020
** can be used as the filename input parameter to these routines:
7021
** <ul>
7022
** <li> [sqlite3_uri_parameter()]
7023
** <li> [sqlite3_uri_boolean()]
7024
** <li> [sqlite3_uri_int64()]
7025
** <li> [sqlite3_filename_database()]
7026
** <li> [sqlite3_filename_journal()]
7027
** <li> [sqlite3_filename_wal()]
7028
** </ul>
7029
*/
7030
SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);
7031
7032
/*
7033
** CAPI3REF: Determine if a database is read-only
7034
** METHOD: sqlite3
7035
**
7036
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
7037
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
7038
** the name of a database on connection D.
7039
*/
7040
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
7041
7042
/*
7043
** CAPI3REF: Determine the transaction state of a database
7044
** METHOD: sqlite3
7045
**
7046
** ^The sqlite3_txn_state(D,S) interface returns the current
7047
** [transaction state] of schema S in database connection D. ^If S is NULL,
7048
** then the highest transaction state of any schema on database connection D
7049
** is returned. Transaction states are (in order of lowest to highest):
7050
** <ol>
7051
** <li value="0"> SQLITE_TXN_NONE
7052
** <li value="1"> SQLITE_TXN_READ
7053
** <li value="2"> SQLITE_TXN_WRITE
7054
** </ol>
7055
** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
7056
** a valid schema, then -1 is returned.
7057
*/
7058
SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
7059
7060
/*
7061
** CAPI3REF: Allowed return values from sqlite3_txn_state()
7062
** KEYWORDS: {transaction state}
7063
**
7064
** These constants define the current transaction state of a database file.
7065
** ^The [sqlite3_txn_state(D,S)] interface returns one of these
7066
** constants in order to describe the transaction state of schema S
7067
** in [database connection] D.
7068
**
7069
** <dl>
7070
** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
7071
** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
7072
** pending.</dd>
7073
**
7074
** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
7075
** <dd>The SQLITE_TXN_READ state means that the database is currently
7076
** in a read transaction. Content has been read from the database file
7077
** but nothing in the database file has changed. The transaction state
7078
** will be advanced to SQLITE_TXN_WRITE if any changes occur and there are
7079
** no other conflicting concurrent write transactions. The transaction
7080
** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
7081
** [COMMIT].</dd>
7082
**
7083
** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
7084
** <dd>The SQLITE_TXN_WRITE state means that the database is currently
7085
** in a write transaction. Content has been written to the database file
7086
** but has not yet committed. The transaction state will change to
7087
** SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
7088
*/
7089
#define SQLITE_TXN_NONE 0
7090
#define SQLITE_TXN_READ 1
7091
#define SQLITE_TXN_WRITE 2
7092
7093
/*
7094
** CAPI3REF: Find the next prepared statement
7095
** METHOD: sqlite3
7096
**
7097
** ^This interface returns a pointer to the next [prepared statement] after
7098
** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
7099
** then this interface returns a pointer to the first prepared statement
7100
** associated with the database connection pDb. ^If no prepared statement
7101
** satisfies the conditions of this routine, it returns NULL.
7102
**
7103
** The [database connection] pointer D in a call to
7104
** [sqlite3_next_stmt(D,S)] must refer to an open database
7105
** connection and in particular must not be a NULL pointer.
7106
*/
7107
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
7108
7109
/*
7110
** CAPI3REF: Commit And Rollback Notification Callbacks
7111
** METHOD: sqlite3
7112
**
7113
** ^The sqlite3_commit_hook() interface registers a callback
7114
** function to be invoked whenever a transaction is [COMMIT | committed].
7115
** ^Any callback set by a previous call to sqlite3_commit_hook()
7116
** for the same database connection is overridden.
7117
** ^The sqlite3_rollback_hook() interface registers a callback
7118
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
7119
** ^Any callback set by a previous call to sqlite3_rollback_hook()
7120
** for the same database connection is overridden.
7121
** ^The pArg argument is passed through to the callback.
7122
** ^If the callback on a commit hook function returns non-zero,
7123
** then the commit is converted into a rollback.
7124
**
7125
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
7126
** return the P argument from the previous call of the same function
7127
** on the same [database connection] D, or NULL for
7128
** the first call for each function on D.
7129
**
7130
** The commit and rollback hook callbacks are not reentrant.
7131
** The callback implementation must not do anything that will modify
7132
** the database connection that invoked the callback. Any actions
7133
** to modify the database connection must be deferred until after the
7134
** completion of the [sqlite3_step()] call that triggered the commit
7135
** or rollback hook in the first place.
7136
** Note that running any other SQL statements, including SELECT statements,
7137
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
7138
** the database connections for the meaning of "modify" in this paragraph.
7139
**
7140
** ^Registering a NULL function disables the callback.
7141
**
7142
** ^When the commit hook callback routine returns zero, the [COMMIT]
7143
** operation is allowed to continue normally. ^If the commit hook
7144
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
7145
** ^The rollback hook is invoked on a rollback that results from a commit
7146
** hook returning non-zero, just as it would be with any other rollback.
7147
**
7148
** ^For the purposes of this API, a transaction is said to have been
7149
** rolled back if an explicit "ROLLBACK" statement is executed, or
7150
** an error or constraint causes an implicit rollback to occur.
7151
** ^The rollback callback is not invoked if a transaction is
7152
** automatically rolled back because the database connection is closed.
7153
**
7154
** See also the [sqlite3_update_hook()] interface.
7155
*/
7156
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
7157
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
7158
7159
/*
7160
** CAPI3REF: Autovacuum Compaction Amount Callback
7161
** METHOD: sqlite3
7162
**
7163
** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
7164
** function C that is invoked prior to each autovacuum of the database
7165
** file. ^The callback is passed a copy of the generic data pointer (P),
7166
** the schema-name of the attached database that is being autovacuumed,
7167
** the size of the database file in pages, the number of free pages,
7168
** and the number of bytes per page, respectively. The callback should
7169
** return the number of free pages that should be removed by the
7170
** autovacuum. ^If the callback returns zero, then no autovacuum happens.
7171
** ^If the value returned is greater than or equal to the number of
7172
** free pages, then a complete autovacuum happens.
7173
**
7174
** <p>^If there are multiple ATTACH-ed database files that are being
7175
** modified as part of a transaction commit, then the autovacuum pages
7176
** callback is invoked separately for each file.
7177
**
7178
** <p><b>The callback is not reentrant.</b> The callback function should
7179
** not attempt to invoke any other SQLite interface. If it does, bad
7180
** things may happen, including segmentation faults and corrupt database
7181
** files. The callback function should be a simple function that
7182
** does some arithmetic on its input parameters and returns a result.
7183
**
7184
** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
7185
** destructor for the P parameter. ^If X is not NULL, then X(P) is
7186
** invoked whenever the database connection closes or when the callback
7187
** is overwritten by another invocation of sqlite3_autovacuum_pages().
7188
**
7189
** <p>^There is only one autovacuum pages callback per database connection.
7190
** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
7191
** previous invocations for that database connection. ^If the callback
7192
** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
7193
** then the autovacuum steps callback is canceled. The return value
7194
** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
7195
** be some other error code if something goes wrong. The current
7196
** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
7197
** return codes might be added in future releases.
7198
**
7199
** <p>If no autovacuum pages callback is specified (the usual case) or
7200
** a NULL pointer is provided for the callback,
7201
** then the default behavior is to vacuum all free pages. So, in other
7202
** words, the default behavior is the same as if the callback function
7203
** were something like this:
7204
**
7205
** <blockquote><pre>
7206
** &nbsp; unsigned int demonstration_autovac_pages_callback(
7207
** &nbsp; void *pClientData,
7208
** &nbsp; const char *zSchema,
7209
** &nbsp; unsigned int nDbPage,
7210
** &nbsp; unsigned int nFreePage,
7211
** &nbsp; unsigned int nBytePerPage
7212
** &nbsp; ){
7213
** &nbsp; return nFreePage;
7214
** &nbsp; }
7215
** </pre></blockquote>
7216
*/
7217
SQLITE_API int sqlite3_autovacuum_pages(
7218
sqlite3 *db,
7219
unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
7220
void*,
7221
void(*)(void*)
7222
);
7223
7224
7225
/*
7226
** CAPI3REF: Data Change Notification Callbacks
7227
** METHOD: sqlite3
7228
**
7229
** ^The sqlite3_update_hook() interface registers a callback function
7230
** with the [database connection] identified by the first argument
7231
** to be invoked whenever a row is updated, inserted or deleted in
7232
** a [rowid table].
7233
** ^Any callback set by a previous call to this function
7234
** for the same database connection is overridden.
7235
**
7236
** ^The second argument is a pointer to the function to invoke when a
7237
** row is updated, inserted or deleted in a rowid table.
7238
** ^The update hook is disabled by invoking sqlite3_update_hook()
7239
** with a NULL pointer as the second parameter.
7240
** ^The first argument to the callback is a copy of the third argument
7241
** to sqlite3_update_hook().
7242
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
7243
** or [SQLITE_UPDATE], depending on the operation that caused the callback
7244
** to be invoked.
7245
** ^The third and fourth arguments to the callback contain pointers to the
7246
** database and table name containing the affected row.
7247
** ^The final callback parameter is the [rowid] of the row.
7248
** ^In the case of an update, this is the [rowid] after the update takes place.
7249
**
7250
** ^(The update hook is not invoked when internal system tables are
7251
** modified (i.e. sqlite_sequence).)^
7252
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
7253
**
7254
** ^In the current implementation, the update hook
7255
** is not invoked when conflicting rows are deleted because of an
7256
** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
7257
** invoked when rows are deleted using the [truncate optimization].
7258
** The exceptions defined in this paragraph might change in a future
7259
** release of SQLite.
7260
**
7261
** Whether the update hook is invoked before or after the
7262
** corresponding change is currently unspecified and may differ
7263
** depending on the type of change. Do not rely on the order of the
7264
** hook call with regards to the final result of the operation which
7265
** triggers the hook.
7266
**
7267
** The update hook implementation must not do anything that will modify
7268
** the database connection that invoked the update hook. Any actions
7269
** to modify the database connection must be deferred until after the
7270
** completion of the [sqlite3_step()] call that triggered the update hook.
7271
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
7272
** database connections for the meaning of "modify" in this paragraph.
7273
**
7274
** ^The sqlite3_update_hook(D,C,P) function
7275
** returns the P argument from the previous call
7276
** on the same [database connection] D, or NULL for
7277
** the first call on D.
7278
**
7279
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
7280
** and [sqlite3_preupdate_hook()] interfaces.
7281
*/
7282
SQLITE_API void *sqlite3_update_hook(
7283
sqlite3*,
7284
void(*)(void *,int ,char const *,char const *,sqlite3_int64),
7285
void*
7286
);
7287
7288
/*
7289
** CAPI3REF: Enable Or Disable Shared Pager Cache
7290
**
7291
** ^(This routine enables or disables the sharing of the database cache
7292
** and schema data structures between [database connection | connections]
7293
** to the same database. Sharing is enabled if the argument is true
7294
** and disabled if the argument is false.)^
7295
**
7296
** This interface is omitted if SQLite is compiled with
7297
** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE]
7298
** compile-time option is recommended because the
7299
** [use of shared cache mode is discouraged].
7300
**
7301
** ^Cache sharing is enabled and disabled for an entire process.
7302
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
7303
** In prior versions of SQLite,
7304
** sharing was enabled or disabled for each thread separately.
7305
**
7306
** ^(The cache sharing mode set by this interface effects all subsequent
7307
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
7308
** Existing database connections continue to use the sharing mode
7309
** that was in effect at the time they were opened.)^
7310
**
7311
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
7312
** successfully. An [error code] is returned otherwise.)^
7313
**
7314
** ^Shared cache is disabled by default. It is recommended that it stay
7315
** that way. In other words, do not use this routine. This interface
7316
** continues to be provided for historical compatibility, but its use is
7317
** discouraged. Any use of shared cache is discouraged. If shared cache
7318
** must be used, it is recommended that shared cache only be enabled for
7319
** individual database connections using the [sqlite3_open_v2()] interface
7320
** with the [SQLITE_OPEN_SHAREDCACHE] flag.
7321
**
7322
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
7323
** and will always return SQLITE_MISUSE. On those systems,
7324
** shared cache mode should be enabled per-database connection via
7325
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
7326
**
7327
** This interface is threadsafe on processors where writing a
7328
** 32-bit integer is atomic.
7329
**
7330
** See Also: [SQLite Shared-Cache Mode]
7331
*/
7332
SQLITE_API int sqlite3_enable_shared_cache(int);
7333
7334
/*
7335
** CAPI3REF: Attempt To Free Heap Memory
7336
**
7337
** ^The sqlite3_release_memory() interface attempts to free N bytes
7338
** of heap memory by deallocating non-essential memory allocations
7339
** held by the database library. Memory used to cache database
7340
** pages to improve performance is an example of non-essential memory.
7341
** ^sqlite3_release_memory() returns the number of bytes actually freed,
7342
** which might be more or less than the amount requested.
7343
** ^The sqlite3_release_memory() routine is a no-op returning zero
7344
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
7345
**
7346
** See also: [sqlite3_db_release_memory()]
7347
*/
7348
SQLITE_API int sqlite3_release_memory(int);
7349
7350
/*
7351
** CAPI3REF: Free Memory Used By A Database Connection
7352
** METHOD: sqlite3
7353
**
7354
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
7355
** memory as possible from database connection D. Unlike the
7356
** [sqlite3_release_memory()] interface, this interface is in effect even
7357
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
7358
** omitted.
7359
**
7360
** See also: [sqlite3_release_memory()]
7361
*/
7362
SQLITE_API int sqlite3_db_release_memory(sqlite3*);
7363
7364
/*
7365
** CAPI3REF: Impose A Limit On Heap Size
7366
**
7367
** These interfaces impose limits on the amount of heap memory that will be
7368
** used by all database connections within a single process.
7369
**
7370
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
7371
** soft limit on the amount of heap memory that may be allocated by SQLite.
7372
** ^SQLite strives to keep heap memory utilization below the soft heap
7373
** limit by reducing the number of pages held in the page cache
7374
** as heap memory usages approaches the limit.
7375
** ^The soft heap limit is "soft" because even though SQLite strives to stay
7376
** below the limit, it will exceed the limit rather than generate
7377
** an [SQLITE_NOMEM] error. In other words, the soft heap limit
7378
** is advisory only.
7379
**
7380
** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
7381
** N bytes on the amount of memory that will be allocated. ^The
7382
** sqlite3_hard_heap_limit64(N) interface is similar to
7383
** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
7384
** when the hard heap limit is reached.
7385
**
7386
** ^The return value from both sqlite3_soft_heap_limit64() and
7387
** sqlite3_hard_heap_limit64() is the size of
7388
** the heap limit prior to the call, or negative in the case of an
7389
** error. ^If the argument N is negative
7390
** then no change is made to the heap limit. Hence, the current
7391
** size of heap limits can be determined by invoking
7392
** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
7393
**
7394
** ^Setting the heap limits to zero disables the heap limiter mechanism.
7395
**
7396
** ^The soft heap limit may not be greater than the hard heap limit.
7397
** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
7398
** is invoked with a value of N that is greater than the hard heap limit,
7399
** the soft heap limit is set to the value of the hard heap limit.
7400
** ^The soft heap limit is automatically enabled whenever the hard heap
7401
** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
7402
** the soft heap limit is outside the range of 1..N, then the soft heap
7403
** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the
7404
** hard heap limit is enabled makes the soft heap limit equal to the
7405
** hard heap limit.
7406
**
7407
** The memory allocation limits can also be adjusted using
7408
** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
7409
**
7410
** ^(The heap limits are not enforced in the current implementation
7411
** if one or more of following conditions are true:
7412
**
7413
** <ul>
7414
** <li> The limit value is set to zero.
7415
** <li> Memory accounting is disabled using a combination of the
7416
** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
7417
** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
7418
** <li> An alternative page cache implementation is specified using
7419
** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
7420
** <li> The page cache allocates from its own memory pool supplied
7421
** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
7422
** from the heap.
7423
** </ul>)^
7424
**
7425
** The circumstances under which SQLite will enforce the heap limits may
7426
** change in future releases of SQLite.
7427
*/
7428
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
7429
SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
7430
7431
/*
7432
** CAPI3REF: Deprecated Soft Heap Limit Interface
7433
** DEPRECATED
7434
**
7435
** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
7436
** interface. This routine is provided for historical compatibility
7437
** only. All new applications should use the
7438
** [sqlite3_soft_heap_limit64()] interface rather than this one.
7439
*/
7440
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
7441
7442
7443
/*
7444
** CAPI3REF: Extract Metadata About A Column Of A Table
7445
** METHOD: sqlite3
7446
**
7447
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
7448
** information about column C of table T in database D
7449
** on [database connection] X.)^ ^The sqlite3_table_column_metadata()
7450
** interface returns SQLITE_OK and fills in the non-NULL pointers in
7451
** the final five arguments with appropriate values if the specified
7452
** column exists. ^The sqlite3_table_column_metadata() interface returns
7453
** SQLITE_ERROR if the specified column does not exist.
7454
** ^If the column-name parameter to sqlite3_table_column_metadata() is a
7455
** NULL pointer, then this routine simply checks for the existence of the
7456
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
7457
** does not. If the table name parameter T in a call to
7458
** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
7459
** undefined behavior.
7460
**
7461
** ^The column is identified by the second, third and fourth parameters to
7462
** this function. ^(The second parameter is either the name of the database
7463
** (i.e. "main", "temp", or an attached database) containing the specified
7464
** table or NULL.)^ ^If it is NULL, then all attached databases are searched
7465
** for the table using the same algorithm used by the database engine to
7466
** resolve unqualified table references.
7467
**
7468
** ^The third and fourth parameters to this function are the table and column
7469
** name of the desired column, respectively.
7470
**
7471
** ^Metadata is returned by writing to the memory locations passed as the 5th
7472
** and subsequent parameters to this function. ^Any of these arguments may be
7473
** NULL, in which case the corresponding element of metadata is omitted.
7474
**
7475
** ^(<blockquote>
7476
** <table border="1">
7477
** <tr><th> Parameter <th> Output<br>Type <th> Description
7478
**
7479
** <tr><td> 5th <td> const char* <td> Data type
7480
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
7481
** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
7482
** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
7483
** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
7484
** </table>
7485
** </blockquote>)^
7486
**
7487
** ^The memory pointed to by the character pointers returned for the
7488
** declaration type and collation sequence is valid until the next
7489
** call to any SQLite API function.
7490
**
7491
** ^If the specified table is actually a view, an [error code] is returned.
7492
**
7493
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
7494
** is not a [WITHOUT ROWID] table and an
7495
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
7496
** parameters are set for the explicitly declared column. ^(If there is no
7497
** [INTEGER PRIMARY KEY] column, then the outputs
7498
** for the [rowid] are set as follows:
7499
**
7500
** <pre>
7501
** data type: "INTEGER"
7502
** collation sequence: "BINARY"
7503
** not null: 0
7504
** primary key: 1
7505
** auto increment: 0
7506
** </pre>)^
7507
**
7508
** ^This function causes all database schemas to be read from disk and
7509
** parsed, if that has not already been done, and returns an error if
7510
** any errors are encountered while loading the schema.
7511
*/
7512
SQLITE_API int sqlite3_table_column_metadata(
7513
sqlite3 *db, /* Connection handle */
7514
const char *zDbName, /* Database name or NULL */
7515
const char *zTableName, /* Table name */
7516
const char *zColumnName, /* Column name */
7517
char const **pzDataType, /* OUTPUT: Declared data type */
7518
char const **pzCollSeq, /* OUTPUT: Collation sequence name */
7519
int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
7520
int *pPrimaryKey, /* OUTPUT: True if column part of PK */
7521
int *pAutoinc /* OUTPUT: True if column is auto-increment */
7522
);
7523
7524
/*
7525
** CAPI3REF: Load An Extension
7526
** METHOD: sqlite3
7527
**
7528
** ^This interface loads an SQLite extension library from the named file.
7529
**
7530
** ^The sqlite3_load_extension() interface attempts to load an
7531
** [SQLite extension] library contained in the file zFile. If
7532
** the file cannot be loaded directly, attempts are made to load
7533
** with various operating-system specific filename extensions added.
7534
** So for example, if "samplelib" cannot be loaded, then names like
7535
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
7536
** be tried also.
7537
**
7538
** ^The entry point is zProc.
7539
** ^(zProc may be 0, in which case SQLite will try to come up with an
7540
** entry point name on its own. It first tries "sqlite3_extension_init".
7541
** If that does not work, it tries names of the form "sqlite3_X_init"
7542
** where X consists of the lower-case equivalent of all ASCII alphabetic
7543
** characters or all ASCII alphanumeric characters in the filename from
7544
** the last "/" to the first following "." and omitting any initial "lib".)^
7545
** ^The sqlite3_load_extension() interface returns
7546
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
7547
** ^If an error occurs and pzErrMsg is not 0, then the
7548
** [sqlite3_load_extension()] interface shall attempt to
7549
** fill *pzErrMsg with error message text stored in memory
7550
** obtained from [sqlite3_malloc()]. The calling function
7551
** should free this memory by calling [sqlite3_free()].
7552
**
7553
** ^Extension loading must be enabled using
7554
** [sqlite3_enable_load_extension()] or
7555
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
7556
** prior to calling this API,
7557
** otherwise an error will be returned.
7558
**
7559
** <b>Security warning:</b> It is recommended that the
7560
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
7561
** interface. The use of the [sqlite3_enable_load_extension()] interface
7562
** should be avoided. This will keep the SQL function [load_extension()]
7563
** disabled and prevent SQL injections from giving attackers
7564
** access to extension loading capabilities.
7565
**
7566
** See also the [load_extension() SQL function].
7567
*/
7568
SQLITE_API int sqlite3_load_extension(
7569
sqlite3 *db, /* Load the extension into this database connection */
7570
const char *zFile, /* Name of the shared library containing extension */
7571
const char *zProc, /* Entry point. Derived from zFile if 0 */
7572
char **pzErrMsg /* Put error message here if not 0 */
7573
);
7574
7575
/*
7576
** CAPI3REF: Enable Or Disable Extension Loading
7577
** METHOD: sqlite3
7578
**
7579
** ^So as not to open security holes in older applications that are
7580
** unprepared to deal with [extension loading], and as a means of disabling
7581
** [extension loading] while evaluating user-entered SQL, the following API
7582
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
7583
**
7584
** ^Extension loading is off by default.
7585
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
7586
** to turn extension loading on and call it with onoff==0 to turn
7587
** it back off again.
7588
**
7589
** ^This interface enables or disables both the C-API
7590
** [sqlite3_load_extension()] and the SQL function [load_extension()].
7591
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
7592
** to enable or disable only the C-API.)^
7593
**
7594
** <b>Security warning:</b> It is recommended that extension loading
7595
** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
7596
** rather than this interface, so the [load_extension()] SQL function
7597
** remains disabled. This will prevent SQL injections from giving attackers
7598
** access to extension loading capabilities.
7599
*/
7600
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
7601
7602
/*
7603
** CAPI3REF: Automatically Load Statically Linked Extensions
7604
**
7605
** ^This interface causes the xEntryPoint() function to be invoked for
7606
** each new [database connection] that is created. The idea here is that
7607
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
7608
** that is to be automatically loaded into all new database connections.
7609
**
7610
** ^(Even though the function prototype shows that xEntryPoint() takes
7611
** no arguments and returns void, SQLite invokes xEntryPoint() with three
7612
** arguments and expects an integer result as if the signature of the
7613
** entry point were as follows:
7614
**
7615
** <blockquote><pre>
7616
** &nbsp; int xEntryPoint(
7617
** &nbsp; sqlite3 *db,
7618
** &nbsp; const char **pzErrMsg,
7619
** &nbsp; const struct sqlite3_api_routines *pThunk
7620
** &nbsp; );
7621
** </pre></blockquote>)^
7622
**
7623
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
7624
** point to an appropriate error message (obtained from [sqlite3_mprintf()])
7625
** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
7626
** is NULL before calling the xEntryPoint(). ^SQLite will invoke
7627
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
7628
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
7629
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
7630
**
7631
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
7632
** on the list of automatic extensions is a harmless no-op. ^No entry point
7633
** will be called more than once for each database connection that is opened.
7634
**
7635
** See also: [sqlite3_reset_auto_extension()]
7636
** and [sqlite3_cancel_auto_extension()]
7637
*/
7638
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
7639
7640
/*
7641
** CAPI3REF: Cancel Automatic Extension Loading
7642
**
7643
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
7644
** initialization routine X that was registered using a prior call to
7645
** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]
7646
** routine returns 1 if initialization routine X was successfully
7647
** unregistered and it returns 0 if X was not on the list of initialization
7648
** routines.
7649
*/
7650
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
7651
7652
/*
7653
** CAPI3REF: Reset Automatic Extension Loading
7654
**
7655
** ^This interface disables all automatic extensions previously
7656
** registered using [sqlite3_auto_extension()].
7657
*/
7658
SQLITE_API void sqlite3_reset_auto_extension(void);
7659
7660
/*
7661
** Structures used by the virtual table interface
7662
*/
7663
typedef struct sqlite3_vtab sqlite3_vtab;
7664
typedef struct sqlite3_index_info sqlite3_index_info;
7665
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
7666
typedef struct sqlite3_module sqlite3_module;
7667
7668
/*
7669
** CAPI3REF: Virtual Table Object
7670
** KEYWORDS: sqlite3_module {virtual table module}
7671
**
7672
** This structure, sometimes called a "virtual table module",
7673
** defines the implementation of a [virtual table].
7674
** This structure consists mostly of methods for the module.
7675
**
7676
** ^A virtual table module is created by filling in a persistent
7677
** instance of this structure and passing a pointer to that instance
7678
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
7679
** ^The registration remains valid until it is replaced by a different
7680
** module or until the [database connection] closes. The content
7681
** of this structure must not change while it is registered with
7682
** any database connection.
7683
*/
7684
struct sqlite3_module {
7685
int iVersion;
7686
int (*xCreate)(sqlite3*, void *pAux,
7687
int argc, const char *const*argv,
7688
sqlite3_vtab **ppVTab, char**);
7689
int (*xConnect)(sqlite3*, void *pAux,
7690
int argc, const char *const*argv,
7691
sqlite3_vtab **ppVTab, char**);
7692
int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
7693
int (*xDisconnect)(sqlite3_vtab *pVTab);
7694
int (*xDestroy)(sqlite3_vtab *pVTab);
7695
int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
7696
int (*xClose)(sqlite3_vtab_cursor*);
7697
int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
7698
int argc, sqlite3_value **argv);
7699
int (*xNext)(sqlite3_vtab_cursor*);
7700
int (*xEof)(sqlite3_vtab_cursor*);
7701
int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
7702
int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
7703
int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
7704
int (*xBegin)(sqlite3_vtab *pVTab);
7705
int (*xSync)(sqlite3_vtab *pVTab);
7706
int (*xCommit)(sqlite3_vtab *pVTab);
7707
int (*xRollback)(sqlite3_vtab *pVTab);
7708
int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
7709
void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
7710
void **ppArg);
7711
int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
7712
/* The methods above are in version 1 of the sqlite_module object. Those
7713
** below are for version 2 and greater. */
7714
int (*xSavepoint)(sqlite3_vtab *pVTab, int);
7715
int (*xRelease)(sqlite3_vtab *pVTab, int);
7716
int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
7717
/* The methods above are in versions 1 and 2 of the sqlite_module object.
7718
** Those below are for version 3 and greater. */
7719
int (*xShadowName)(const char*);
7720
/* The methods above are in versions 1 through 3 of the sqlite_module object.
7721
** Those below are for version 4 and greater. */
7722
int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
7723
const char *zTabName, int mFlags, char **pzErr);
7724
};
7725
7726
/*
7727
** CAPI3REF: Virtual Table Indexing Information
7728
** KEYWORDS: sqlite3_index_info
7729
**
7730
** The sqlite3_index_info structure and its substructures is used as part
7731
** of the [virtual table] interface to
7732
** pass information into and receive the reply from the [xBestIndex]
7733
** method of a [virtual table module]. The fields under **Inputs** are the
7734
** inputs to xBestIndex and are read-only. xBestIndex inserts its
7735
** results into the **Outputs** fields.
7736
**
7737
** ^(The aConstraint[] array records WHERE clause constraints of the form:
7738
**
7739
** <blockquote>column OP expr</blockquote>
7740
**
7741
** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^ ^(The particular operator is
7742
** stored in aConstraint[].op using one of the
7743
** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
7744
** ^(The index of the column is stored in
7745
** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
7746
** expr on the right-hand side can be evaluated (and thus the constraint
7747
** is usable) and false if it cannot.)^
7748
**
7749
** ^The optimizer automatically inverts terms of the form "expr OP column"
7750
** and makes other simplifications to the WHERE clause in an attempt to
7751
** get as many WHERE clause terms into the form shown above as possible.
7752
** ^The aConstraint[] array only reports WHERE clause terms that are
7753
** relevant to the particular virtual table being queried.
7754
**
7755
** ^Information about the ORDER BY clause is stored in aOrderBy[].
7756
** ^Each term of aOrderBy records a column of the ORDER BY clause.
7757
**
7758
** The colUsed field indicates which columns of the virtual table may be
7759
** required by the current scan. Virtual table columns are numbered from
7760
** zero in the order in which they appear within the CREATE TABLE statement
7761
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
7762
** the corresponding bit is set within the colUsed mask if the column may be
7763
** required by SQLite. If the table has at least 64 columns and any column
7764
** to the right of the first 63 is required, then bit 63 of colUsed is also
7765
** set. In other words, column iCol may be required if the expression
7766
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
7767
** non-zero.
7768
**
7769
** The [xBestIndex] method must fill aConstraintUsage[] with information
7770
** about what parameters to pass to xFilter. ^If argvIndex>0 then
7771
** the right-hand side of the corresponding aConstraint[] is evaluated
7772
** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
7773
** is true, then the constraint is assumed to be fully handled by the
7774
** virtual table and might not be checked again by the byte code.)^ ^(The
7775
** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
7776
** is left in its default setting of false, the constraint will always be
7777
** checked separately in byte code. If the omit flag is changed to true, then
7778
** the constraint may or may not be checked in byte code. In other words,
7779
** when the omit flag is true there is no guarantee that the constraint will
7780
** not be checked again using byte code.)^
7781
**
7782
** ^The idxNum and idxStr values are recorded and passed into the
7783
** [xFilter] method.
7784
** ^[sqlite3_free()] is used to free idxStr if and only if
7785
** needToFreeIdxStr is true.
7786
**
7787
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
7788
** the correct order to satisfy the ORDER BY clause so that no separate
7789
** sorting step is required.
7790
**
7791
** ^The estimatedCost value is an estimate of the cost of a particular
7792
** strategy. A cost of N indicates that the cost of the strategy is similar
7793
** to a linear scan of an SQLite table with N rows. A cost of log(N)
7794
** indicates that the expense of the operation is similar to that of a
7795
** binary search on a unique indexed field of an SQLite table with N rows.
7796
**
7797
** ^The estimatedRows value is an estimate of the number of rows that
7798
** will be returned by the strategy.
7799
**
7800
** The xBestIndex method may optionally populate the idxFlags field with a
7801
** mask of SQLITE_INDEX_SCAN_* flags. One such flag is
7802
** [SQLITE_INDEX_SCAN_HEX], which if set causes the [EXPLAIN QUERY PLAN]
7803
** output to show the idxNum as hex instead of as decimal. Another flag is
7804
** SQLITE_INDEX_SCAN_UNIQUE, which if set indicates that the query plan will
7805
** return at most one row.
7806
**
7807
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
7808
** SQLite also assumes that if a call to the xUpdate() method is made as
7809
** part of the same statement to delete or update a virtual table row and the
7810
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
7811
** any database changes. In other words, if the xUpdate() returns
7812
** SQLITE_CONSTRAINT, the database contents must be exactly as they were
7813
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
7814
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
7815
** the xUpdate method are automatically rolled back by SQLite.
7816
**
7817
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
7818
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
7819
** If a virtual table extension is
7820
** used with an SQLite version earlier than 3.8.2, the results of attempting
7821
** to read or write the estimatedRows field are undefined (but are likely
7822
** to include crashing the application). The estimatedRows field should
7823
** therefore only be used if [sqlite3_libversion_number()] returns a
7824
** value greater than or equal to 3008002. Similarly, the idxFlags field
7825
** was added for [version 3.9.0] ([dateof:3.9.0]).
7826
** It may therefore only be used if
7827
** sqlite3_libversion_number() returns a value greater than or equal to
7828
** 3009000.
7829
*/
7830
struct sqlite3_index_info {
7831
/* Inputs */
7832
int nConstraint; /* Number of entries in aConstraint */
7833
struct sqlite3_index_constraint {
7834
int iColumn; /* Column constrained. -1 for ROWID */
7835
unsigned char op; /* Constraint operator */
7836
unsigned char usable; /* True if this constraint is usable */
7837
int iTermOffset; /* Used internally - xBestIndex should ignore */
7838
} *aConstraint; /* Table of WHERE clause constraints */
7839
int nOrderBy; /* Number of terms in the ORDER BY clause */
7840
struct sqlite3_index_orderby {
7841
int iColumn; /* Column number */
7842
unsigned char desc; /* True for DESC. False for ASC. */
7843
} *aOrderBy; /* The ORDER BY clause */
7844
/* Outputs */
7845
struct sqlite3_index_constraint_usage {
7846
int argvIndex; /* if >0, constraint is part of argv to xFilter */
7847
unsigned char omit; /* Do not code a test for this constraint */
7848
} *aConstraintUsage;
7849
int idxNum; /* Number used to identify the index */
7850
char *idxStr; /* String, possibly obtained from sqlite3_malloc */
7851
int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
7852
int orderByConsumed; /* True if output is already ordered */
7853
double estimatedCost; /* Estimated cost of using this index */
7854
/* Fields below are only available in SQLite 3.8.2 and later */
7855
sqlite3_int64 estimatedRows; /* Estimated number of rows returned */
7856
/* Fields below are only available in SQLite 3.9.0 and later */
7857
int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */
7858
/* Fields below are only available in SQLite 3.10.0 and later */
7859
sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */
7860
};
7861
7862
/*
7863
** CAPI3REF: Virtual Table Scan Flags
7864
**
7865
** Virtual table implementations are allowed to set the
7866
** [sqlite3_index_info].idxFlags field to some combination of
7867
** these bits.
7868
*/
7869
#define SQLITE_INDEX_SCAN_UNIQUE 0x00000001 /* Scan visits at most 1 row */
7870
#define SQLITE_INDEX_SCAN_HEX 0x00000002 /* Display idxNum as hex */
7871
/* in EXPLAIN QUERY PLAN */
7872
7873
/*
7874
** CAPI3REF: Virtual Table Constraint Operator Codes
7875
**
7876
** These macros define the allowed values for the
7877
** [sqlite3_index_info].aConstraint[].op field. Each value represents
7878
** an operator that is part of a constraint term in the WHERE clause of
7879
** a query that uses a [virtual table].
7880
**
7881
** ^The left-hand operand of the operator is given by the corresponding
7882
** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand
7883
** operand is the rowid.
7884
** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
7885
** operators have no left-hand operand, and so for those operators the
7886
** corresponding aConstraint[].iColumn is meaningless and should not be
7887
** used.
7888
**
7889
** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
7890
** value 255 are reserved to represent functions that are overloaded
7891
** by the [xFindFunction|xFindFunction method] of the virtual table
7892
** implementation.
7893
**
7894
** The right-hand operands for each constraint might be accessible using
7895
** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand
7896
** operand is only available if it appears as a single constant literal
7897
** in the input SQL. If the right-hand operand is another column or an
7898
** expression (even a constant expression) or a parameter, then the
7899
** sqlite3_vtab_rhs_value() probably will not be able to extract it.
7900
** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
7901
** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
7902
** and hence calls to sqlite3_vtab_rhs_value() for those operators will
7903
** always return SQLITE_NOTFOUND.
7904
**
7905
** The collating sequence to be used for comparison can be found using
7906
** the [sqlite3_vtab_collation()] interface. For most real-world virtual
7907
** tables, the collating sequence of constraints does not matter (for example
7908
** because the constraints are numeric) and so the sqlite3_vtab_collation()
7909
** interface is not commonly needed.
7910
*/
7911
#define SQLITE_INDEX_CONSTRAINT_EQ 2
7912
#define SQLITE_INDEX_CONSTRAINT_GT 4
7913
#define SQLITE_INDEX_CONSTRAINT_LE 8
7914
#define SQLITE_INDEX_CONSTRAINT_LT 16
7915
#define SQLITE_INDEX_CONSTRAINT_GE 32
7916
#define SQLITE_INDEX_CONSTRAINT_MATCH 64
7917
#define SQLITE_INDEX_CONSTRAINT_LIKE 65
7918
#define SQLITE_INDEX_CONSTRAINT_GLOB 66
7919
#define SQLITE_INDEX_CONSTRAINT_REGEXP 67
7920
#define SQLITE_INDEX_CONSTRAINT_NE 68
7921
#define SQLITE_INDEX_CONSTRAINT_ISNOT 69
7922
#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70
7923
#define SQLITE_INDEX_CONSTRAINT_ISNULL 71
7924
#define SQLITE_INDEX_CONSTRAINT_IS 72
7925
#define SQLITE_INDEX_CONSTRAINT_LIMIT 73
7926
#define SQLITE_INDEX_CONSTRAINT_OFFSET 74
7927
#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150
7928
7929
/*
7930
** CAPI3REF: Register A Virtual Table Implementation
7931
** METHOD: sqlite3
7932
**
7933
** ^These routines are used to register a new [virtual table module] name.
7934
** ^Module names must be registered before
7935
** creating a new [virtual table] using the module and before using a
7936
** preexisting [virtual table] for the module.
7937
**
7938
** ^The module name is registered on the [database connection] specified
7939
** by the first parameter. ^The name of the module is given by the
7940
** second parameter. ^The third parameter is a pointer to
7941
** the implementation of the [virtual table module]. ^The fourth
7942
** parameter is an arbitrary client data pointer that is passed through
7943
** into the [xCreate] and [xConnect] methods of the virtual table module
7944
** when a new virtual table is being created or reinitialized.
7945
**
7946
** ^The sqlite3_create_module_v2() interface has a fifth parameter which
7947
** is a pointer to a destructor for the pClientData. ^SQLite will
7948
** invoke the destructor function (if it is not NULL) when SQLite
7949
** no longer needs the pClientData pointer. ^The destructor will also
7950
** be invoked if the call to sqlite3_create_module_v2() fails.
7951
** ^The sqlite3_create_module()
7952
** interface is equivalent to sqlite3_create_module_v2() with a NULL
7953
** destructor.
7954
**
7955
** ^If the third parameter (the pointer to the sqlite3_module object) is
7956
** NULL then no new module is created and any existing modules with the
7957
** same name are dropped.
7958
**
7959
** See also: [sqlite3_drop_modules()]
7960
*/
7961
SQLITE_API int sqlite3_create_module(
7962
sqlite3 *db, /* SQLite connection to register module with */
7963
const char *zName, /* Name of the module */
7964
const sqlite3_module *p, /* Methods for the module */
7965
void *pClientData /* Client data for xCreate/xConnect */
7966
);
7967
SQLITE_API int sqlite3_create_module_v2(
7968
sqlite3 *db, /* SQLite connection to register module with */
7969
const char *zName, /* Name of the module */
7970
const sqlite3_module *p, /* Methods for the module */
7971
void *pClientData, /* Client data for xCreate/xConnect */
7972
void(*xDestroy)(void*) /* Module destructor function */
7973
);
7974
7975
/*
7976
** CAPI3REF: Remove Unnecessary Virtual Table Implementations
7977
** METHOD: sqlite3
7978
**
7979
** ^The sqlite3_drop_modules(D,L) interface removes all virtual
7980
** table modules from database connection D except those named on list L.
7981
** The L parameter must be either NULL or a pointer to an array of pointers
7982
** to strings where the array is terminated by a single NULL pointer.
7983
** ^If the L parameter is NULL, then all virtual table modules are removed.
7984
**
7985
** See also: [sqlite3_create_module()]
7986
*/
7987
SQLITE_API int sqlite3_drop_modules(
7988
sqlite3 *db, /* Remove modules from this connection */
7989
const char **azKeep /* Except, do not remove the ones named here */
7990
);
7991
7992
/*
7993
** CAPI3REF: Virtual Table Instance Object
7994
** KEYWORDS: sqlite3_vtab
7995
**
7996
** Every [virtual table module] implementation uses a subclass
7997
** of this object to describe a particular instance
7998
** of the [virtual table]. Each subclass will
7999
** be tailored to the specific needs of the module implementation.
8000
** The purpose of this superclass is to define certain fields that are
8001
** common to all module implementations.
8002
**
8003
** ^Virtual tables methods can set an error message by assigning a
8004
** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
8005
** take care that any prior string is freed by a call to [sqlite3_free()]
8006
** prior to assigning a new string to zErrMsg. ^After the error message
8007
** is delivered up to the client application, the string will be automatically
8008
** freed by sqlite3_free() and the zErrMsg field will be zeroed.
8009
*/
8010
struct sqlite3_vtab {
8011
const sqlite3_module *pModule; /* The module for this virtual table */
8012
int nRef; /* Number of open cursors */
8013
char *zErrMsg; /* Error message from sqlite3_mprintf() */
8014
/* Virtual table implementations will typically add additional fields */
8015
};
8016
8017
/*
8018
** CAPI3REF: Virtual Table Cursor Object
8019
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
8020
**
8021
** Every [virtual table module] implementation uses a subclass of the
8022
** following structure to describe cursors that point into the
8023
** [virtual table] and are used
8024
** to loop through the virtual table. Cursors are created using the
8025
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
8026
** by the [sqlite3_module.xClose | xClose] method. Cursors are used
8027
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
8028
** of the module. Each module implementation will define
8029
** the content of a cursor structure to suit its own needs.
8030
**
8031
** This superclass exists in order to define fields of the cursor that
8032
** are common to all implementations.
8033
*/
8034
struct sqlite3_vtab_cursor {
8035
sqlite3_vtab *pVtab; /* Virtual table of this cursor */
8036
/* Virtual table implementations will typically add additional fields */
8037
};
8038
8039
/*
8040
** CAPI3REF: Declare The Schema Of A Virtual Table
8041
**
8042
** ^The [xCreate] and [xConnect] methods of a
8043
** [virtual table module] call this interface
8044
** to declare the format (the names and datatypes of the columns) of
8045
** the virtual tables they implement.
8046
*/
8047
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
8048
8049
/*
8050
** CAPI3REF: Overload A Function For A Virtual Table
8051
** METHOD: sqlite3
8052
**
8053
** ^(Virtual tables can provide alternative implementations of functions
8054
** using the [xFindFunction] method of the [virtual table module].
8055
** But global versions of those functions
8056
** must exist in order to be overloaded.)^
8057
**
8058
** ^(This API makes sure a global version of a function with a particular
8059
** name and number of parameters exists. If no such function exists
8060
** before this API is called, a new function is created.)^ ^The implementation
8061
** of the new function always causes an exception to be thrown. So
8062
** the new function is not good for anything by itself. Its only
8063
** purpose is to be a placeholder function that can be overloaded
8064
** by a [virtual table].
8065
*/
8066
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
8067
8068
/*
8069
** CAPI3REF: A Handle To An Open BLOB
8070
** KEYWORDS: {BLOB handle} {BLOB handles}
8071
**
8072
** An instance of this object represents an open BLOB on which
8073
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
8074
** ^Objects of this type are created by [sqlite3_blob_open()]
8075
** and destroyed by [sqlite3_blob_close()].
8076
** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
8077
** can be used to read or write small subsections of the BLOB.
8078
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
8079
*/
8080
typedef struct sqlite3_blob sqlite3_blob;
8081
8082
/*
8083
** CAPI3REF: Open A BLOB For Incremental I/O
8084
** METHOD: sqlite3
8085
** CONSTRUCTOR: sqlite3_blob
8086
**
8087
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
8088
** in row iRow, column zColumn, table zTable in database zDb;
8089
** in other words, the same BLOB that would be selected by:
8090
**
8091
** <pre>
8092
** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
8093
** </pre>)^
8094
**
8095
** ^(Parameter zDb is not the filename that contains the database, but
8096
** rather the symbolic name of the database. For attached databases, this is
8097
** the name that appears after the AS keyword in the [ATTACH] statement.
8098
** For the main database file, the database name is "main". For TEMP
8099
** tables, the database name is "temp".)^
8100
**
8101
** ^If the flags parameter is non-zero, then the BLOB is opened for read
8102
** and write access. ^If the flags parameter is zero, the BLOB is opened for
8103
** read-only access.
8104
**
8105
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
8106
** in *ppBlob. Otherwise an [error code] is returned and, unless the error
8107
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
8108
** the API is not misused, it is always safe to call [sqlite3_blob_close()]
8109
** on *ppBlob after this function returns.
8110
**
8111
** This function fails with SQLITE_ERROR if any of the following are true:
8112
** <ul>
8113
** <li> ^(Database zDb does not exist)^,
8114
** <li> ^(Table zTable does not exist within database zDb)^,
8115
** <li> ^(Table zTable is a WITHOUT ROWID table)^,
8116
** <li> ^(Column zColumn does not exist)^,
8117
** <li> ^(Row iRow is not present in the table)^,
8118
** <li> ^(The specified column of row iRow contains a value that is not
8119
** a TEXT or BLOB value)^,
8120
** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
8121
** constraint and the blob is being opened for read/write access)^,
8122
** <li> ^([foreign key constraints | Foreign key constraints] are enabled,
8123
** column zColumn is part of a [child key] definition and the blob is
8124
** being opened for read/write access)^.
8125
** </ul>
8126
**
8127
** ^Unless it returns SQLITE_MISUSE, this function sets the
8128
** [database connection] error code and message accessible via
8129
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
8130
**
8131
** A BLOB referenced by sqlite3_blob_open() may be read using the
8132
** [sqlite3_blob_read()] interface and modified by using
8133
** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a
8134
** different row of the same table using the [sqlite3_blob_reopen()]
8135
** interface. However, the column, table, or database of a [BLOB handle]
8136
** cannot be changed after the [BLOB handle] is opened.
8137
**
8138
** ^(If the row that a BLOB handle points to is modified by an
8139
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
8140
** then the BLOB handle is marked as "expired".
8141
** This is true if any column of the row is changed, even a column
8142
** other than the one the BLOB handle is open on.)^
8143
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
8144
** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
8145
** ^(Changes written into a BLOB prior to the BLOB expiring are not
8146
** rolled back by the expiration of the BLOB. Such changes will eventually
8147
** commit if the transaction continues to completion.)^
8148
**
8149
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
8150
** the opened blob. ^The size of a blob may not be changed by this
8151
** interface. Use the [UPDATE] SQL command to change the size of a
8152
** blob.
8153
**
8154
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
8155
** and the built-in [zeroblob] SQL function may be used to create a
8156
** zero-filled blob to read or write using the incremental-blob interface.
8157
**
8158
** To avoid a resource leak, every open [BLOB handle] should eventually
8159
** be released by a call to [sqlite3_blob_close()].
8160
**
8161
** See also: [sqlite3_blob_close()],
8162
** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
8163
** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
8164
*/
8165
SQLITE_API int sqlite3_blob_open(
8166
sqlite3*,
8167
const char *zDb,
8168
const char *zTable,
8169
const char *zColumn,
8170
sqlite3_int64 iRow,
8171
int flags,
8172
sqlite3_blob **ppBlob
8173
);
8174
8175
/*
8176
** CAPI3REF: Move a BLOB Handle to a New Row
8177
** METHOD: sqlite3_blob
8178
**
8179
** ^This function is used to move an existing [BLOB handle] so that it points
8180
** to a different row of the same database table. ^The new row is identified
8181
** by the rowid value passed as the second argument. Only the row can be
8182
** changed. ^The database, table and column on which the blob handle is open
8183
** remain the same. Moving an existing [BLOB handle] to a new row is
8184
** faster than closing the existing handle and opening a new one.
8185
**
8186
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
8187
** it must exist and there must be either a blob or text value stored in
8188
** the nominated column.)^ ^If the new row is not present in the table, or if
8189
** it does not contain a blob or text value, or if another error occurs, an
8190
** SQLite error code is returned and the blob handle is considered aborted.
8191
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
8192
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
8193
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
8194
** always returns zero.
8195
**
8196
** ^This function sets the database handle error code and message.
8197
*/
8198
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
8199
8200
/*
8201
** CAPI3REF: Close A BLOB Handle
8202
** DESTRUCTOR: sqlite3_blob
8203
**
8204
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
8205
** unconditionally. Even if this routine returns an error code, the
8206
** handle is still closed.)^
8207
**
8208
** ^If the blob handle being closed was opened for read-write access, and if
8209
** the database is in auto-commit mode and there are no other open read-write
8210
** blob handles or active write statements, the current transaction is
8211
** committed. ^If an error occurs while committing the transaction, an error
8212
** code is returned and the transaction rolled back.
8213
**
8214
** Calling this function with an argument that is not a NULL pointer or an
8215
** open blob handle results in undefined behavior. ^Calling this routine
8216
** with a null pointer (such as would be returned by a failed call to
8217
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
8218
** is passed a valid open blob handle, the values returned by the
8219
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
8220
*/
8221
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
8222
8223
/*
8224
** CAPI3REF: Return The Size Of An Open BLOB
8225
** METHOD: sqlite3_blob
8226
**
8227
** ^Returns the size in bytes of the BLOB accessible via the
8228
** successfully opened [BLOB handle] in its only argument. ^The
8229
** incremental blob I/O routines can only read or overwrite existing
8230
** blob content; they cannot change the size of a blob.
8231
**
8232
** This routine only works on a [BLOB handle] which has been created
8233
** by a prior successful call to [sqlite3_blob_open()] and which has not
8234
** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8235
** to this routine results in undefined and probably undesirable behavior.
8236
*/
8237
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
8238
8239
/*
8240
** CAPI3REF: Read Data From A BLOB Incrementally
8241
** METHOD: sqlite3_blob
8242
**
8243
** ^(This function is used to read data from an open [BLOB handle] into a
8244
** caller-supplied buffer. N bytes of data are copied into buffer Z
8245
** from the open BLOB, starting at offset iOffset.)^
8246
**
8247
** ^If offset iOffset is less than N bytes from the end of the BLOB,
8248
** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
8249
** less than zero, [SQLITE_ERROR] is returned and no data is read.
8250
** ^The size of the blob (and hence the maximum value of N+iOffset)
8251
** can be determined using the [sqlite3_blob_bytes()] interface.
8252
**
8253
** ^An attempt to read from an expired [BLOB handle] fails with an
8254
** error code of [SQLITE_ABORT].
8255
**
8256
** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
8257
** Otherwise, an [error code] or an [extended error code] is returned.)^
8258
**
8259
** This routine only works on a [BLOB handle] which has been created
8260
** by a prior successful call to [sqlite3_blob_open()] and which has not
8261
** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8262
** to this routine results in undefined and probably undesirable behavior.
8263
**
8264
** See also: [sqlite3_blob_write()].
8265
*/
8266
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
8267
8268
/*
8269
** CAPI3REF: Write Data Into A BLOB Incrementally
8270
** METHOD: sqlite3_blob
8271
**
8272
** ^(This function is used to write data into an open [BLOB handle] from a
8273
** caller-supplied buffer. N bytes of data are copied from the buffer Z
8274
** into the open BLOB, starting at offset iOffset.)^
8275
**
8276
** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
8277
** Otherwise, an [error code] or an [extended error code] is returned.)^
8278
** ^Unless SQLITE_MISUSE is returned, this function sets the
8279
** [database connection] error code and message accessible via
8280
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
8281
**
8282
** ^If the [BLOB handle] passed as the first argument was not opened for
8283
** writing (the flags parameter to [sqlite3_blob_open()] was zero),
8284
** this function returns [SQLITE_READONLY].
8285
**
8286
** This function may only modify the contents of the BLOB; it is
8287
** not possible to increase the size of a BLOB using this API.
8288
** ^If offset iOffset is less than N bytes from the end of the BLOB,
8289
** [SQLITE_ERROR] is returned and no data is written. The size of the
8290
** BLOB (and hence the maximum value of N+iOffset) can be determined
8291
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
8292
** than zero [SQLITE_ERROR] is returned and no data is written.
8293
**
8294
** ^An attempt to write to an expired [BLOB handle] fails with an
8295
** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
8296
** before the [BLOB handle] expired are not rolled back by the
8297
** expiration of the handle, though of course those changes might
8298
** have been overwritten by the statement that expired the BLOB handle
8299
** or by other independent statements.
8300
**
8301
** This routine only works on a [BLOB handle] which has been created
8302
** by a prior successful call to [sqlite3_blob_open()] and which has not
8303
** been closed by [sqlite3_blob_close()]. Passing any other pointer in
8304
** to this routine results in undefined and probably undesirable behavior.
8305
**
8306
** See also: [sqlite3_blob_read()].
8307
*/
8308
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
8309
8310
/*
8311
** CAPI3REF: Virtual File System Objects
8312
**
8313
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
8314
** that SQLite uses to interact
8315
** with the underlying operating system. Most SQLite builds come with a
8316
** single default VFS that is appropriate for the host computer.
8317
** New VFSes can be registered and existing VFSes can be unregistered.
8318
** The following interfaces are provided.
8319
**
8320
** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
8321
** ^Names are case sensitive.
8322
** ^Names are zero-terminated UTF-8 strings.
8323
** ^If there is no match, a NULL pointer is returned.
8324
** ^If zVfsName is NULL then the default VFS is returned.
8325
**
8326
** ^New VFSes are registered with sqlite3_vfs_register().
8327
** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
8328
** ^The same VFS can be registered multiple times without injury.
8329
** ^To make an existing VFS into the default VFS, register it again
8330
** with the makeDflt flag set. If two different VFSes with the
8331
** same name are registered, the behavior is undefined. If a
8332
** VFS is registered with a name that is NULL or an empty string,
8333
** then the behavior is undefined.
8334
**
8335
** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
8336
** ^(If the default VFS is unregistered, another VFS is chosen as
8337
** the default. The choice for the new VFS is arbitrary.)^
8338
*/
8339
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
8340
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
8341
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
8342
8343
/*
8344
** CAPI3REF: Mutexes
8345
**
8346
** The SQLite core uses these routines for thread
8347
** synchronization. Though they are intended for internal
8348
** use by SQLite, code that links against SQLite is
8349
** permitted to use any of these routines.
8350
**
8351
** The SQLite source code contains multiple implementations
8352
** of these mutex routines. An appropriate implementation
8353
** is selected automatically at compile-time. The following
8354
** implementations are available in the SQLite core:
8355
**
8356
** <ul>
8357
** <li> SQLITE_MUTEX_PTHREADS
8358
** <li> SQLITE_MUTEX_W32
8359
** <li> SQLITE_MUTEX_NOOP
8360
** </ul>
8361
**
8362
** The SQLITE_MUTEX_NOOP implementation is a set of routines
8363
** that does no real locking and is appropriate for use in
8364
** a single-threaded application. The SQLITE_MUTEX_PTHREADS and
8365
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
8366
** and Windows.
8367
**
8368
**
8369
** ^The sqlite3_mutex_alloc() routine allocates a new
8370
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
8371
** routine returns NULL if it is unable to allocate the requested
8372
** mutex. The argument to sqlite3_mutex_alloc() must be one of these
8373
** integer constants:
8374
**
8375
** <ul>
8376
** <li> SQLITE_MUTEX_FAST
8377
** <li> SQLITE_MUTEX_RECURSIVE
8378
** <li> SQLITE_MUTEX_STATIC_MAIN
8379
** <li> SQLITE_MUTEX_STATIC_MEM
8380
** <li> SQLITE_MUTEX_STATIC_OPEN
8381
** <li> SQLITE_MUTEX_STATIC_PRNG
8382
** <li> SQLITE_MUTEX_STATIC_LRU
8383
** <li> SQLITE_MUTEX_STATIC_PMEM
8384
** <li> SQLITE_MUTEX_STATIC_APP1
8385
** <li> SQLITE_MUTEX_STATIC_APP2
8386
** <li> SQLITE_MUTEX_STATIC_APP3
8387
** <li> SQLITE_MUTEX_STATIC_VFS1
8388
** <li> SQLITE_MUTEX_STATIC_VFS2
8389
** <li> SQLITE_MUTEX_STATIC_VFS3
8390
** </ul>
8391
**
8392
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
8393
** cause sqlite3_mutex_alloc() to create
8394
** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
8395
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
8396
** The mutex implementation does not need to make a distinction
8397
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
8398
** not want to. SQLite will only request a recursive mutex in
8399
** cases where it really needs one. If a faster non-recursive mutex
8400
** implementation is available on the host platform, the mutex subsystem
8401
** might return such a mutex in response to SQLITE_MUTEX_FAST.
8402
**
8403
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
8404
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
8405
** a pointer to a static preexisting mutex. ^Nine static mutexes are
8406
** used by the current version of SQLite. Future versions of SQLite
8407
** may add additional static mutexes. Static mutexes are for internal
8408
** use by SQLite only. Applications that use SQLite mutexes should
8409
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
8410
** SQLITE_MUTEX_RECURSIVE.
8411
**
8412
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
8413
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
8414
** returns a different mutex on every call. ^For the static
8415
** mutex types, the same mutex is returned on every call that has
8416
** the same type number.
8417
**
8418
** ^The sqlite3_mutex_free() routine deallocates a previously
8419
** allocated dynamic mutex. Attempting to deallocate a static
8420
** mutex results in undefined behavior.
8421
**
8422
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
8423
** to enter a mutex. ^If another thread is already within the mutex,
8424
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
8425
** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
8426
** upon successful entry. ^(Mutexes created using
8427
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
8428
** In such cases, the
8429
** mutex must be exited an equal number of times before another thread
8430
** can enter.)^ If the same thread tries to enter any mutex other
8431
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
8432
**
8433
** ^(Some systems (for example, Windows 95) do not support the operation
8434
** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
8435
** will always return SQLITE_BUSY. In most cases the SQLite core only uses
8436
** sqlite3_mutex_try() as an optimization, so this is acceptable
8437
** behavior. The exceptions are unix builds that set the
8438
** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working
8439
** sqlite3_mutex_try() is required.)^
8440
**
8441
** ^The sqlite3_mutex_leave() routine exits a mutex that was
8442
** previously entered by the same thread. The behavior
8443
** is undefined if the mutex is not currently entered by the
8444
** calling thread or is not currently allocated.
8445
**
8446
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
8447
** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
8448
** then any of the four routines behaves as a no-op.
8449
**
8450
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
8451
*/
8452
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
8453
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
8454
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
8455
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
8456
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
8457
8458
/*
8459
** CAPI3REF: Mutex Methods Object
8460
**
8461
** An instance of this structure defines the low-level routines
8462
** used to allocate and use mutexes.
8463
**
8464
** Usually, the default mutex implementations provided by SQLite are
8465
** sufficient, however the application has the option of substituting a custom
8466
** implementation for specialized deployments or systems for which SQLite
8467
** does not provide a suitable implementation. In this case, the application
8468
** creates and populates an instance of this structure to pass
8469
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
8470
** Additionally, an instance of this structure can be used as an
8471
** output variable when querying the system for the current mutex
8472
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
8473
**
8474
** ^The xMutexInit method defined by this structure is invoked as
8475
** part of system initialization by the sqlite3_initialize() function.
8476
** ^The xMutexInit routine is called by SQLite exactly once for each
8477
** effective call to [sqlite3_initialize()].
8478
**
8479
** ^The xMutexEnd method defined by this structure is invoked as
8480
** part of system shutdown by the sqlite3_shutdown() function. The
8481
** implementation of this method is expected to release all outstanding
8482
** resources obtained by the mutex methods implementation, especially
8483
** those obtained by the xMutexInit method. ^The xMutexEnd()
8484
** interface is invoked exactly once for each call to [sqlite3_shutdown()].
8485
**
8486
** ^(The remaining seven methods defined by this structure (xMutexAlloc,
8487
** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
8488
** xMutexNotheld) implement the following interfaces (respectively):
8489
**
8490
** <ul>
8491
** <li> [sqlite3_mutex_alloc()] </li>
8492
** <li> [sqlite3_mutex_free()] </li>
8493
** <li> [sqlite3_mutex_enter()] </li>
8494
** <li> [sqlite3_mutex_try()] </li>
8495
** <li> [sqlite3_mutex_leave()] </li>
8496
** <li> [sqlite3_mutex_held()] </li>
8497
** <li> [sqlite3_mutex_notheld()] </li>
8498
** </ul>)^
8499
**
8500
** The only difference is that the public sqlite3_XXX functions enumerated
8501
** above silently ignore any invocations that pass a NULL pointer instead
8502
** of a valid mutex handle. The implementations of the methods defined
8503
** by this structure are not required to handle this case. The results
8504
** of passing a NULL pointer instead of a valid mutex handle are undefined
8505
** (i.e. it is acceptable to provide an implementation that segfaults if
8506
** it is passed a NULL pointer).
8507
**
8508
** The xMutexInit() method must be threadsafe. It must be harmless to
8509
** invoke xMutexInit() multiple times within the same process and without
8510
** intervening calls to xMutexEnd(). Second and subsequent calls to
8511
** xMutexInit() must be no-ops.
8512
**
8513
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
8514
** and its associates). Similarly, xMutexAlloc() must not use SQLite memory
8515
** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
8516
** memory allocation for a fast or recursive mutex.
8517
**
8518
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
8519
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
8520
** If xMutexInit fails in any way, it is expected to clean up after itself
8521
** prior to returning.
8522
*/
8523
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
8524
struct sqlite3_mutex_methods {
8525
int (*xMutexInit)(void);
8526
int (*xMutexEnd)(void);
8527
sqlite3_mutex *(*xMutexAlloc)(int);
8528
void (*xMutexFree)(sqlite3_mutex *);
8529
void (*xMutexEnter)(sqlite3_mutex *);
8530
int (*xMutexTry)(sqlite3_mutex *);
8531
void (*xMutexLeave)(sqlite3_mutex *);
8532
int (*xMutexHeld)(sqlite3_mutex *);
8533
int (*xMutexNotheld)(sqlite3_mutex *);
8534
};
8535
8536
/*
8537
** CAPI3REF: Mutex Verification Routines
8538
**
8539
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
8540
** are intended for use inside assert() statements. The SQLite core
8541
** never uses these routines except inside an assert() and applications
8542
** are advised to follow the lead of the core. The SQLite core only
8543
** provides implementations for these routines when it is compiled
8544
** with the SQLITE_DEBUG flag. External mutex implementations
8545
** are only required to provide these routines if SQLITE_DEBUG is
8546
** defined and if NDEBUG is not defined.
8547
**
8548
** These routines should return true if the mutex in their argument
8549
** is held or not held, respectively, by the calling thread.
8550
**
8551
** The implementation is not required to provide versions of these
8552
** routines that actually work. If the implementation does not provide working
8553
** versions of these routines, it should at least provide stubs that always
8554
** return true so that one does not get spurious assertion failures.
8555
**
8556
** If the argument to sqlite3_mutex_held() is a NULL pointer then
8557
** the routine should return 1. This seems counter-intuitive since
8558
** clearly the mutex cannot be held if it does not exist. But
8559
** the reason the mutex does not exist is because the build is not
8560
** using mutexes. And we do not want the assert() containing the
8561
** call to sqlite3_mutex_held() to fail, so a non-zero return is
8562
** the appropriate thing to do. The sqlite3_mutex_notheld()
8563
** interface should also return 1 when given a NULL pointer.
8564
*/
8565
#ifndef NDEBUG
8566
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
8567
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
8568
#endif
8569
8570
/*
8571
** CAPI3REF: Mutex Types
8572
**
8573
** The [sqlite3_mutex_alloc()] interface takes a single argument
8574
** which is one of these integer constants.
8575
**
8576
** The set of static mutexes may change from one SQLite release to the
8577
** next. Applications that override the built-in mutex logic must be
8578
** prepared to accommodate additional static mutexes.
8579
*/
8580
#define SQLITE_MUTEX_FAST 0
8581
#define SQLITE_MUTEX_RECURSIVE 1
8582
#define SQLITE_MUTEX_STATIC_MAIN 2
8583
#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
8584
#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
8585
#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
8586
#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */
8587
#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
8588
#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
8589
#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
8590
#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */
8591
#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */
8592
#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */
8593
#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */
8594
#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */
8595
#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */
8596
8597
/* Legacy compatibility: */
8598
#define SQLITE_MUTEX_STATIC_MASTER 2
8599
8600
8601
/*
8602
** CAPI3REF: Retrieve the mutex for a database connection
8603
** METHOD: sqlite3
8604
**
8605
** ^This interface returns a pointer to the [sqlite3_mutex] object that
8606
** serializes access to the [database connection] given in the argument
8607
** when the [threading mode] is Serialized.
8608
** ^If the [threading mode] is Single-thread or Multi-thread then this
8609
** routine returns a NULL pointer.
8610
*/
8611
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
8612
8613
/*
8614
** CAPI3REF: Low-Level Control Of Database Files
8615
** METHOD: sqlite3
8616
** KEYWORDS: {file control}
8617
**
8618
** ^The [sqlite3_file_control()] interface makes a direct call to the
8619
** xFileControl method for the [sqlite3_io_methods] object associated
8620
** with a particular database identified by the second argument. ^The
8621
** name of the database is "main" for the main database or "temp" for the
8622
** TEMP database, or the name that appears after the AS keyword for
8623
** databases that are added using the [ATTACH] SQL command.
8624
** ^A NULL pointer can be used in place of "main" to refer to the
8625
** main database file.
8626
** ^The third and fourth parameters to this routine
8627
** are passed directly through to the second and third parameters of
8628
** the xFileControl method. ^The return value of the xFileControl
8629
** method becomes the return value of this routine.
8630
**
8631
** A few opcodes for [sqlite3_file_control()] are handled directly
8632
** by the SQLite core and never invoke the
8633
** sqlite3_io_methods.xFileControl method.
8634
** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
8635
** a pointer to the underlying [sqlite3_file] object to be written into
8636
** the space pointed to by the 4th parameter. The
8637
** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
8638
** the [sqlite3_file] object associated with the journal file instead of
8639
** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns
8640
** a pointer to the underlying [sqlite3_vfs] object for the file.
8641
** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
8642
** from the pager.
8643
**
8644
** ^If the second parameter (zDbName) does not match the name of any
8645
** open database file, then SQLITE_ERROR is returned. ^This error
8646
** code is not remembered and will not be recalled by [sqlite3_errcode()]
8647
** or [sqlite3_errmsg()]. The underlying xFileControl method might
8648
** also return SQLITE_ERROR. There is no way to distinguish between
8649
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
8650
** xFileControl method.
8651
**
8652
** See also: [file control opcodes]
8653
*/
8654
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
8655
8656
/*
8657
** CAPI3REF: Testing Interface
8658
**
8659
** ^The sqlite3_test_control() interface is used to read out internal
8660
** state of SQLite and to inject faults into SQLite for testing
8661
** purposes. ^The first parameter is an operation code that determines
8662
** the number, meaning, and operation of all subsequent parameters.
8663
**
8664
** This interface is not for use by applications. It exists solely
8665
** for verifying the correct operation of the SQLite library. Depending
8666
** on how the SQLite library is compiled, this interface might not exist.
8667
**
8668
** The details of the operation codes, their meanings, the parameters
8669
** they take, and what they do are all subject to change without notice.
8670
** Unlike most of the SQLite API, this function is not guaranteed to
8671
** operate consistently from one release to the next.
8672
*/
8673
SQLITE_API int sqlite3_test_control(int op, ...);
8674
8675
/*
8676
** CAPI3REF: Testing Interface Operation Codes
8677
**
8678
** These constants are the valid operation code parameters used
8679
** as the first argument to [sqlite3_test_control()].
8680
**
8681
** These parameters and their meanings are subject to change
8682
** without notice. These values are for testing purposes only.
8683
** Applications should not use any of these parameters or the
8684
** [sqlite3_test_control()] interface.
8685
*/
8686
#define SQLITE_TESTCTRL_FIRST 5
8687
#define SQLITE_TESTCTRL_PRNG_SAVE 5
8688
#define SQLITE_TESTCTRL_PRNG_RESTORE 6
8689
#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */
8690
#define SQLITE_TESTCTRL_FK_NO_ACTION 7
8691
#define SQLITE_TESTCTRL_BITVEC_TEST 8
8692
#define SQLITE_TESTCTRL_FAULT_INSTALL 9
8693
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
8694
#define SQLITE_TESTCTRL_PENDING_BYTE 11
8695
#define SQLITE_TESTCTRL_ASSERT 12
8696
#define SQLITE_TESTCTRL_ALWAYS 13
8697
#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */
8698
#define SQLITE_TESTCTRL_JSON_SELFCHECK 14
8699
#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
8700
#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */
8701
#define SQLITE_TESTCTRL_GETOPT 16
8702
#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */
8703
#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17
8704
#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
8705
#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */
8706
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19
8707
#define SQLITE_TESTCTRL_NEVER_CORRUPT 20
8708
#define SQLITE_TESTCTRL_VDBE_COVERAGE 21
8709
#define SQLITE_TESTCTRL_BYTEORDER 22
8710
#define SQLITE_TESTCTRL_ISINIT 23
8711
#define SQLITE_TESTCTRL_SORTER_MMAP 24
8712
#define SQLITE_TESTCTRL_IMPOSTER 25
8713
#define SQLITE_TESTCTRL_PARSER_COVERAGE 26
8714
#define SQLITE_TESTCTRL_RESULT_INTREAL 27
8715
#define SQLITE_TESTCTRL_PRNG_SEED 28
8716
#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29
8717
#define SQLITE_TESTCTRL_SEEK_COUNT 30
8718
#define SQLITE_TESTCTRL_TRACEFLAGS 31
8719
#define SQLITE_TESTCTRL_TUNE 32
8720
#define SQLITE_TESTCTRL_LOGEST 33
8721
#define SQLITE_TESTCTRL_USELONGDOUBLE 34 /* NOT USED */
8722
#define SQLITE_TESTCTRL_ATOF 34
8723
#define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */
8724
8725
/*
8726
** CAPI3REF: SQL Keyword Checking
8727
**
8728
** These routines provide access to the set of SQL language keywords
8729
** recognized by SQLite. Applications can use these routines to determine
8730
** whether or not a specific identifier needs to be escaped (for example,
8731
** by enclosing in double-quotes) so as not to confuse the parser.
8732
**
8733
** The sqlite3_keyword_count() interface returns the number of distinct
8734
** keywords understood by SQLite.
8735
**
8736
** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and
8737
** makes *Z point to that keyword expressed as UTF8 and writes the number
8738
** of bytes in the keyword into *L. The string that *Z points to is not
8739
** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns
8740
** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
8741
** or L are NULL or invalid pointers then calls to
8742
** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
8743
**
8744
** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
8745
** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
8746
** if it is and zero if not.
8747
**
8748
** The parser used by SQLite is forgiving. It is often possible to use
8749
** a keyword as an identifier as long as such use does not result in a
8750
** parsing ambiguity. For example, the statement
8751
** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
8752
** creates a new table named "BEGIN" with three columns named
8753
** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid
8754
** using keywords as identifiers. Common techniques used to avoid keyword
8755
** name collisions include:
8756
** <ul>
8757
** <li> Put all identifier names inside double-quotes. This is the official
8758
** SQL way to escape identifier names.
8759
** <li> Put identifier names inside &#91;...&#93;. This is not standard SQL,
8760
** but it is what SQL Server does and so lots of programmers use this
8761
** technique.
8762
** <li> Begin every identifier with the letter "Z" as no SQL keywords start
8763
** with "Z".
8764
** <li> Include a digit somewhere in every identifier name.
8765
** </ul>
8766
**
8767
** Note that the number of keywords understood by SQLite can depend on
8768
** compile-time options. For example, "VACUUM" is not a keyword if
8769
** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also,
8770
** new keywords may be added to future releases of SQLite.
8771
*/
8772
SQLITE_API int sqlite3_keyword_count(void);
8773
SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
8774
SQLITE_API int sqlite3_keyword_check(const char*,int);
8775
8776
/*
8777
** CAPI3REF: Dynamic String Object
8778
** KEYWORDS: {dynamic string}
8779
**
8780
** An instance of the sqlite3_str object contains a dynamically-sized
8781
** string under construction.
8782
**
8783
** The lifecycle of an sqlite3_str object is as follows:
8784
** <ol>
8785
** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
8786
** <li> ^Text is appended to the sqlite3_str object using various
8787
** methods, such as [sqlite3_str_appendf()].
8788
** <li> ^The sqlite3_str object is destroyed and the string it created
8789
** is returned using the [sqlite3_str_finish()] interface.
8790
** </ol>
8791
*/
8792
typedef struct sqlite3_str sqlite3_str;
8793
8794
/*
8795
** CAPI3REF: Create A New Dynamic String Object
8796
** CONSTRUCTOR: sqlite3_str
8797
**
8798
** ^The [sqlite3_str_new(D)] interface allocates and initializes
8799
** a new [sqlite3_str] object. To avoid memory leaks, the object returned by
8800
** [sqlite3_str_new()] must be freed by a subsequent call to
8801
** [sqlite3_str_finish(X)].
8802
**
8803
** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
8804
** valid [sqlite3_str] object, though in the event of an out-of-memory
8805
** error the returned object might be a special singleton that will
8806
** silently reject new text, always return SQLITE_NOMEM from
8807
** [sqlite3_str_errcode()], always return 0 for
8808
** [sqlite3_str_length()], and always return NULL from
8809
** [sqlite3_str_finish(X)]. It is always safe to use the value
8810
** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
8811
** to any of the other [sqlite3_str] methods.
8812
**
8813
** The D parameter to [sqlite3_str_new(D)] may be NULL. If the
8814
** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
8815
** length of the string contained in the [sqlite3_str] object will be
8816
** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
8817
** of [SQLITE_MAX_LENGTH].
8818
*/
8819
SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
8820
8821
/*
8822
** CAPI3REF: Finalize A Dynamic String
8823
** DESTRUCTOR: sqlite3_str
8824
**
8825
** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
8826
** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
8827
** that contains the constructed string. The calling application should
8828
** pass the returned value to [sqlite3_free()] to avoid a memory leak.
8829
** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
8830
** errors were encountered during construction of the string. ^The
8831
** [sqlite3_str_finish(X)] interface might also return a NULL pointer if the
8832
** string in [sqlite3_str] object X is zero bytes long.
8833
**
8834
** ^The [sqlite3_str_free(X)] interface destroys both the sqlite3_str object
8835
** X and the string content it contains. Calling sqlite3_str_free(X) is
8836
** the equivalent of calling [sqlite3_free](sqlite3_str_finish(X)).
8837
*/
8838
SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
8839
SQLITE_API void sqlite3_str_free(sqlite3_str*);
8840
8841
/*
8842
** CAPI3REF: Add Content To A Dynamic String
8843
** METHOD: sqlite3_str
8844
**
8845
** These interfaces add or remove content to an sqlite3_str object
8846
** previously obtained from [sqlite3_str_new()].
8847
**
8848
** ^The [sqlite3_str_appendf(X,F,...)] and
8849
** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
8850
** functionality of SQLite to append formatted text onto the end of
8851
** [sqlite3_str] object X.
8852
**
8853
** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
8854
** onto the end of the [sqlite3_str] object X. N must be non-negative.
8855
** S must contain at least N non-zero bytes of content. To append a
8856
** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
8857
** method instead.
8858
**
8859
** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
8860
** zero-terminated string S onto the end of [sqlite3_str] object X.
8861
**
8862
** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
8863
** single-byte character C onto the end of [sqlite3_str] object X.
8864
** ^This method can be used, for example, to add whitespace indentation.
8865
**
8866
** ^The [sqlite3_str_reset(X)] method resets the string under construction
8867
** inside [sqlite3_str] object X back to zero bytes in length.
8868
**
8869
** ^The [sqlite3_str_truncate(X,N)] method changes the length of the string
8870
** under construction to be N bytes or less. This routine is a no-op if
8871
** N is negative or if the string is already N bytes or smaller in size.
8872
**
8873
** These methods do not return a result code. ^If an error occurs, that fact
8874
** is recorded in the [sqlite3_str] object and can be recovered by a
8875
** subsequent call to [sqlite3_str_errcode(X)].
8876
*/
8877
SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
8878
SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
8879
SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
8880
SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
8881
SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
8882
SQLITE_API void sqlite3_str_reset(sqlite3_str*);
8883
SQLITE_API void sqlite3_str_truncate(sqlite3_str*,int N);
8884
8885
/*
8886
** CAPI3REF: Status Of A Dynamic String
8887
** METHOD: sqlite3_str
8888
**
8889
** These interfaces return the current status of an [sqlite3_str] object.
8890
**
8891
** ^If any prior errors have occurred while constructing the dynamic string
8892
** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
8893
** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns
8894
** [SQLITE_NOMEM] following any out-of-memory error, or
8895
** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
8896
** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
8897
**
8898
** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
8899
** of the dynamic string under construction in [sqlite3_str] object X.
8900
** ^The length returned by [sqlite3_str_length(X)] does not include the
8901
** zero-termination byte.
8902
**
8903
** ^The [sqlite3_str_value(X)] method returns a pointer to the current
8904
** content of the dynamic string under construction in X. The value
8905
** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
8906
** and might be freed or altered by any subsequent method on the same
8907
** [sqlite3_str] object. Applications must not use the pointer returned by
8908
** [sqlite3_str_value(X)] after any subsequent method call on the same
8909
** object. ^Applications may change the content of the string returned
8910
** by [sqlite3_str_value(X)] as long as they do not write into any bytes
8911
** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
8912
** write any byte after any subsequent sqlite3_str method call.
8913
*/
8914
SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
8915
SQLITE_API int sqlite3_str_length(sqlite3_str*);
8916
SQLITE_API char *sqlite3_str_value(sqlite3_str*);
8917
8918
/*
8919
** CAPI3REF: SQLite Runtime Status
8920
**
8921
** ^These interfaces are used to retrieve runtime status information
8922
** about the performance of SQLite, and optionally to reset various
8923
** highwater marks. ^The first argument is an integer code for
8924
** the specific parameter to measure. ^(Recognized integer codes
8925
** are of the form [status parameters | SQLITE_STATUS_...].)^
8926
** ^The current value of the parameter is returned into *pCurrent.
8927
** ^The highest recorded value is returned in *pHighwater. ^If the
8928
** resetFlag is true, then the highest record value is reset after
8929
** *pHighwater is written. ^(Some parameters do not record the highest
8930
** value. For those parameters
8931
** nothing is written into *pHighwater and the resetFlag is ignored.)^
8932
** ^(Other parameters record only the highwater mark and not the current
8933
** value. For these latter parameters nothing is written into *pCurrent.)^
8934
**
8935
** ^The sqlite3_status() and sqlite3_status64() routines return
8936
** SQLITE_OK on success and a non-zero [error code] on failure.
8937
**
8938
** If either the current value or the highwater mark is too large to
8939
** be represented by a 32-bit integer, then the values returned by
8940
** sqlite3_status() are undefined.
8941
**
8942
** See also: [sqlite3_db_status()]
8943
*/
8944
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
8945
SQLITE_API int sqlite3_status64(
8946
int op,
8947
sqlite3_int64 *pCurrent,
8948
sqlite3_int64 *pHighwater,
8949
int resetFlag
8950
);
8951
8952
8953
/*
8954
** CAPI3REF: Status Parameters
8955
** KEYWORDS: {status parameters}
8956
**
8957
** These integer constants designate various run-time status parameters
8958
** that can be returned by [sqlite3_status()].
8959
**
8960
** <dl>
8961
** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
8962
** <dd>This parameter is the current amount of memory checked out
8963
** using [sqlite3_malloc()], either directly or indirectly. The
8964
** figure includes calls made to [sqlite3_malloc()] by the application
8965
** and internal memory usage by the SQLite library. Auxiliary page-cache
8966
** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
8967
** this parameter. The amount returned is the sum of the allocation
8968
** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
8969
**
8970
** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
8971
** <dd>This parameter records the largest memory allocation request
8972
** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
8973
** internal equivalents). Only the value returned in the
8974
** *pHighwater parameter to [sqlite3_status()] is of interest.
8975
** The value written into the *pCurrent parameter is undefined.</dd>)^
8976
**
8977
** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
8978
** <dd>This parameter records the number of separate memory allocations
8979
** currently checked out.</dd>)^
8980
**
8981
** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
8982
** <dd>This parameter returns the number of pages used out of the
8983
** [pagecache memory allocator] that was configured using
8984
** [SQLITE_CONFIG_PAGECACHE]. The
8985
** value returned is in pages, not in bytes.</dd>)^
8986
**
8987
** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
8988
** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
8989
** <dd>This parameter returns the number of bytes of page cache
8990
** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
8991
** buffer and where forced to overflow to [sqlite3_malloc()]. The
8992
** returned value includes allocations that overflowed because they
8993
** were too large (they were larger than the "sz" parameter to
8994
** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
8995
** no space was left in the page cache.</dd>)^
8996
**
8997
** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
8998
** <dd>This parameter records the largest memory allocation request
8999
** handed to the [pagecache memory allocator]. Only the value returned in the
9000
** *pHighwater parameter to [sqlite3_status()] is of interest.
9001
** The value written into the *pCurrent parameter is undefined.</dd>)^
9002
**
9003
** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
9004
** <dd>No longer used.</dd>
9005
**
9006
** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
9007
** <dd>No longer used.</dd>
9008
**
9009
** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
9010
** <dd>No longer used.</dd>
9011
**
9012
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
9013
** <dd>The *pHighwater parameter records the deepest parser stack.
9014
** The *pCurrent value is undefined. The *pHighwater value is only
9015
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
9016
** </dl>
9017
**
9018
** New status parameters may be added from time to time.
9019
*/
9020
#define SQLITE_STATUS_MEMORY_USED 0
9021
#define SQLITE_STATUS_PAGECACHE_USED 1
9022
#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
9023
#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */
9024
#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */
9025
#define SQLITE_STATUS_MALLOC_SIZE 5
9026
#define SQLITE_STATUS_PARSER_STACK 6
9027
#define SQLITE_STATUS_PAGECACHE_SIZE 7
9028
#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */
9029
#define SQLITE_STATUS_MALLOC_COUNT 9
9030
9031
/*
9032
** CAPI3REF: Database Connection Status
9033
** METHOD: sqlite3
9034
**
9035
** ^This interface is used to retrieve runtime status information
9036
** about a single [database connection]. ^The first argument is the
9037
** database connection object to be interrogated. ^The second argument
9038
** is an integer constant, taken from the set of
9039
** [SQLITE_DBSTATUS options], that
9040
** determines the parameter to interrogate. The set of
9041
** [SQLITE_DBSTATUS options] is likely
9042
** to grow in future releases of SQLite.
9043
**
9044
** ^The current value of the requested parameter is written into *pCur
9045
** and the highest instantaneous value is written into *pHiwtr. ^If
9046
** the resetFlg is true, then the highest instantaneous value is
9047
** reset back down to the current value.
9048
**
9049
** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
9050
** non-zero [error code] on failure.
9051
**
9052
** ^The sqlite3_db_status64(D,O,C,H,R) routine works exactly the same
9053
** way as sqlite3_db_status(D,O,C,H,R) routine except that the C and H
9054
** parameters are pointer to 64-bit integers (type: sqlite3_int64) instead
9055
** of pointers to 32-bit integers, which allows larger status values
9056
** to be returned. If a status value exceeds 2,147,483,647 then
9057
** sqlite3_db_status() will truncate the value whereas sqlite3_db_status64()
9058
** will return the full value.
9059
**
9060
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
9061
*/
9062
SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
9063
SQLITE_API int sqlite3_db_status64(sqlite3*,int,sqlite3_int64*,sqlite3_int64*,int);
9064
9065
/*
9066
** CAPI3REF: Status Parameters for database connections
9067
** KEYWORDS: {SQLITE_DBSTATUS options}
9068
**
9069
** These constants are the available integer "verbs" that can be passed as
9070
** the second argument to the [sqlite3_db_status()] interface.
9071
**
9072
** New verbs may be added in future releases of SQLite. Existing verbs
9073
** might be discontinued. Applications should check the return code from
9074
** [sqlite3_db_status()] to make sure that the call worked.
9075
** The [sqlite3_db_status()] interface will return a non-zero error code
9076
** if a discontinued or unsupported verb is invoked.
9077
**
9078
** <dl>
9079
** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
9080
** <dd>This parameter returns the number of lookaside memory slots currently
9081
** checked out.</dd>)^
9082
**
9083
** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
9084
** <dd>This parameter returns the number of malloc attempts that were
9085
** satisfied using lookaside memory. Only the high-water value is meaningful;
9086
** the current value is always zero.</dd>)^
9087
**
9088
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
9089
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
9090
** <dd>This parameter returns the number of malloc attempts that might have
9091
** been satisfied using lookaside memory but failed due to the amount of
9092
** memory requested being larger than the lookaside slot size.
9093
** Only the high-water value is meaningful;
9094
** the current value is always zero.</dd>)^
9095
**
9096
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
9097
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
9098
** <dd>This parameter returns the number of malloc attempts that might have
9099
** been satisfied using lookaside memory but failed due to all lookaside
9100
** memory already being in use.
9101
** Only the high-water value is meaningful;
9102
** the current value is always zero.</dd>)^
9103
**
9104
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
9105
** <dd>This parameter returns the approximate number of bytes of heap
9106
** memory used by all pager caches associated with the database connection.)^
9107
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
9108
** </dd>
9109
**
9110
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
9111
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
9112
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
9113
** pager cache is shared between two or more connections the bytes of heap
9114
** memory used by that pager cache is divided evenly between the attached
9115
** connections.)^ In other words, if none of the pager caches associated
9116
** with the database connection are shared, this request returns the same
9117
** value as DBSTATUS_CACHE_USED. Or, if one or more of the pager caches are
9118
** shared, the value returned by this call will be smaller than that returned
9119
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
9120
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.</dd>
9121
**
9122
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
9123
** <dd>This parameter returns the approximate number of bytes of heap
9124
** memory used to store the schema for all databases associated
9125
** with the connection - main, temp, and any [ATTACH]-ed databases.)^
9126
** ^The full amount of memory used by the schemas is reported, even if the
9127
** schema memory is shared with other database connections due to
9128
** [shared cache mode] being enabled.
9129
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
9130
** </dd>
9131
**
9132
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
9133
** <dd>This parameter returns the approximate number of bytes of heap
9134
** and lookaside memory used by all prepared statements associated with
9135
** the database connection.)^
9136
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
9137
** </dd>
9138
**
9139
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
9140
** <dd>This parameter returns the number of pager cache hits that have
9141
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
9142
** is always 0.
9143
** </dd>
9144
**
9145
** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
9146
** <dd>This parameter returns the number of pager cache misses that have
9147
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
9148
** is always 0.
9149
** </dd>
9150
**
9151
** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
9152
** <dd>This parameter returns the number of dirty cache entries that have
9153
** been written to disk. Specifically, the number of pages written to the
9154
** wal file in wal mode databases, or the number of pages written to the
9155
** database file in rollback mode databases. Any pages written as part of
9156
** transaction rollback or database recovery operations are not included.
9157
** If an IO or other error occurs while writing a page to disk, the effect
9158
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
9159
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
9160
** <p>
9161
** ^(There is overlap between the quantities measured by this parameter
9162
** (SQLITE_DBSTATUS_CACHE_WRITE) and SQLITE_DBSTATUS_TEMPBUF_SPILL.
9163
** Resetting one will reduce the other.)^
9164
** </dd>
9165
**
9166
** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
9167
** <dd>This parameter returns the number of dirty cache entries that have
9168
** been written to disk in the middle of a transaction due to the page
9169
** cache overflowing. Transactions are more efficient if they are written
9170
** to disk all at once. When pages spill mid-transaction, that introduces
9171
** additional overhead. This parameter can be used to help identify
9172
** inefficiencies that can be resolved by increasing the cache size.
9173
** </dd>
9174
**
9175
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
9176
** <dd>This parameter returns zero for the current value if and only if
9177
** all foreign key constraints (deferred or immediate) have been
9178
** resolved.)^ ^The highwater mark is always 0.
9179
**
9180
** [[SQLITE_DBSTATUS_TEMPBUF_SPILL] ^(<dt>SQLITE_DBSTATUS_TEMPBUF_SPILL</dt>
9181
** <dd>^(This parameter returns the number of bytes written to temporary
9182
** files on disk that could have been kept in memory had sufficient memory
9183
** been available. This value includes writes to intermediate tables that
9184
** are part of complex queries, external sorts that spill to disk, and
9185
** writes to TEMP tables.)^
9186
** ^The highwater mark is always 0.
9187
** <p>
9188
** ^(There is overlap between the quantities measured by this parameter
9189
** (SQLITE_DBSTATUS_TEMPBUF_SPILL) and SQLITE_DBSTATUS_CACHE_WRITE.
9190
** Resetting one will reduce the other.)^
9191
** </dd>
9192
** </dl>
9193
*/
9194
#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
9195
#define SQLITE_DBSTATUS_CACHE_USED 1
9196
#define SQLITE_DBSTATUS_SCHEMA_USED 2
9197
#define SQLITE_DBSTATUS_STMT_USED 3
9198
#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
9199
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
9200
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
9201
#define SQLITE_DBSTATUS_CACHE_HIT 7
9202
#define SQLITE_DBSTATUS_CACHE_MISS 8
9203
#define SQLITE_DBSTATUS_CACHE_WRITE 9
9204
#define SQLITE_DBSTATUS_DEFERRED_FKS 10
9205
#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11
9206
#define SQLITE_DBSTATUS_CACHE_SPILL 12
9207
#define SQLITE_DBSTATUS_TEMPBUF_SPILL 13
9208
#define SQLITE_DBSTATUS_MAX 13 /* Largest defined DBSTATUS */
9209
9210
9211
/*
9212
** CAPI3REF: Prepared Statement Status
9213
** METHOD: sqlite3_stmt
9214
**
9215
** ^(Each prepared statement maintains various
9216
** [SQLITE_STMTSTATUS counters] that measure the number
9217
** of times it has performed specific operations.)^ These counters can
9218
** be used to monitor the performance characteristics of the prepared
9219
** statements. For example, if the number of table steps greatly exceeds
9220
** the number of table searches or result rows, that would tend to indicate
9221
** that the prepared statement is using a full table scan rather than
9222
** an index.
9223
**
9224
** ^(This interface is used to retrieve and reset counter values from
9225
** a [prepared statement]. The first argument is the prepared statement
9226
** object to be interrogated. The second argument
9227
** is an integer code for a specific [SQLITE_STMTSTATUS counter]
9228
** to be interrogated.)^
9229
** ^The current value of the requested counter is returned.
9230
** ^If the resetFlg is true, then the counter is reset to zero after this
9231
** interface call returns.
9232
**
9233
** See also: [sqlite3_status()] and [sqlite3_db_status()].
9234
*/
9235
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
9236
9237
/*
9238
** CAPI3REF: Status Parameters for prepared statements
9239
** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
9240
**
9241
** These preprocessor macros define integer codes that name counter
9242
** values associated with the [sqlite3_stmt_status()] interface.
9243
** The meanings of the various counters are as follows:
9244
**
9245
** <dl>
9246
** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
9247
** <dd>^This is the number of times that SQLite has stepped forward in
9248
** a table as part of a full table scan. Large numbers for this counter
9249
** may indicate opportunities for performance improvement through
9250
** careful use of indices.</dd>
9251
**
9252
** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
9253
** <dd>^This is the number of sort operations that have occurred.
9254
** A non-zero value in this counter may indicate an opportunity to
9255
** improve performance through careful use of indices.</dd>
9256
**
9257
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
9258
** <dd>^This is the number of rows inserted into transient indices that
9259
** were created automatically in order to help joins run faster.
9260
** A non-zero value in this counter may indicate an opportunity to
9261
** improve performance by adding permanent indices that do not
9262
** need to be reinitialized each time the statement is run.</dd>
9263
**
9264
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
9265
** <dd>^This is the number of virtual machine operations executed
9266
** by the prepared statement if that number is less than or equal
9267
** to 2147483647. The number of virtual machine operations can be
9268
** used as a proxy for the total work done by the prepared statement.
9269
** If the number of virtual machine operations exceeds 2147483647
9270
** then the value returned by this statement status code is undefined.</dd>
9271
**
9272
** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
9273
** <dd>^This is the number of times that the prepare statement has been
9274
** automatically regenerated due to schema changes or changes to
9275
** [bound parameters] that might affect the query plan.</dd>
9276
**
9277
** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
9278
** <dd>^This is the number of times that the prepared statement has
9279
** been run. A single "run" for the purposes of this counter is one
9280
** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
9281
** The counter is incremented on the first [sqlite3_step()] call of each
9282
** cycle.</dd>
9283
**
9284
** [[SQLITE_STMTSTATUS_FILTER_MISS]]
9285
** [[SQLITE_STMTSTATUS_FILTER HIT]]
9286
** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br>
9287
** SQLITE_STMTSTATUS_FILTER_MISS</dt>
9288
** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join
9289
** step was bypassed because a Bloom filter returned not-found. The
9290
** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of
9291
** times that the Bloom filter returned a find, and thus the join step
9292
** had to be processed as normal.</dd>
9293
**
9294
** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
9295
** <dd>^This is the approximate number of bytes of heap memory
9296
** used to store the prepared statement. ^This value is not actually
9297
** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
9298
** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
9299
** </dd>
9300
** </dl>
9301
*/
9302
#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
9303
#define SQLITE_STMTSTATUS_SORT 2
9304
#define SQLITE_STMTSTATUS_AUTOINDEX 3
9305
#define SQLITE_STMTSTATUS_VM_STEP 4
9306
#define SQLITE_STMTSTATUS_REPREPARE 5
9307
#define SQLITE_STMTSTATUS_RUN 6
9308
#define SQLITE_STMTSTATUS_FILTER_MISS 7
9309
#define SQLITE_STMTSTATUS_FILTER_HIT 8
9310
#define SQLITE_STMTSTATUS_MEMUSED 99
9311
9312
/*
9313
** CAPI3REF: Custom Page Cache Object
9314
**
9315
** The sqlite3_pcache type is opaque. It is implemented by
9316
** the pluggable module. The SQLite core has no knowledge of
9317
** its size or internal structure and never deals with the
9318
** sqlite3_pcache object except by holding and passing pointers
9319
** to the object.
9320
**
9321
** See [sqlite3_pcache_methods2] for additional information.
9322
*/
9323
typedef struct sqlite3_pcache sqlite3_pcache;
9324
9325
/*
9326
** CAPI3REF: Custom Page Cache Object
9327
**
9328
** The sqlite3_pcache_page object represents a single page in the
9329
** page cache. The page cache will allocate instances of this
9330
** object. Various methods of the page cache use pointers to instances
9331
** of this object as parameters or as their return value.
9332
**
9333
** See [sqlite3_pcache_methods2] for additional information.
9334
*/
9335
typedef struct sqlite3_pcache_page sqlite3_pcache_page;
9336
struct sqlite3_pcache_page {
9337
void *pBuf; /* The content of the page */
9338
void *pExtra; /* Extra information associated with the page */
9339
};
9340
9341
/*
9342
** CAPI3REF: Application Defined Page Cache.
9343
** KEYWORDS: {page cache}
9344
**
9345
** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
9346
** register an alternative page cache implementation by passing in an
9347
** instance of the sqlite3_pcache_methods2 structure.)^
9348
** In many applications, most of the heap memory allocated by
9349
** SQLite is used for the page cache.
9350
** By implementing a
9351
** custom page cache using this API, an application can better control
9352
** the amount of memory consumed by SQLite, the way in which
9353
** that memory is allocated and released, and the policies used to
9354
** determine exactly which parts of a database file are cached and for
9355
** how long.
9356
**
9357
** The alternative page cache mechanism is an
9358
** extreme measure that is only needed by the most demanding applications.
9359
** The built-in page cache is recommended for most uses.
9360
**
9361
** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
9362
** internal buffer by SQLite within the call to [sqlite3_config]. Hence
9363
** the application may discard the parameter after the call to
9364
** [sqlite3_config()] returns.)^
9365
**
9366
** [[the xInit() page cache method]]
9367
** ^(The xInit() method is called once for each effective
9368
** call to [sqlite3_initialize()])^
9369
** (usually only once during the lifetime of the process). ^(The xInit()
9370
** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
9371
** The intent of the xInit() method is to set up global data structures
9372
** required by the custom page cache implementation.
9373
** ^(If the xInit() method is NULL, then the
9374
** built-in default page cache is used instead of the application defined
9375
** page cache.)^
9376
**
9377
** [[the xShutdown() page cache method]]
9378
** ^The xShutdown() method is called by [sqlite3_shutdown()].
9379
** It can be used to clean up
9380
** any outstanding resources before process shutdown, if required.
9381
** ^The xShutdown() method may be NULL.
9382
**
9383
** ^SQLite automatically serializes calls to the xInit method,
9384
** so the xInit method need not be threadsafe. ^The
9385
** xShutdown method is only called from [sqlite3_shutdown()] so it does
9386
** not need to be threadsafe either. All other methods must be threadsafe
9387
** in multithreaded applications.
9388
**
9389
** ^SQLite will never invoke xInit() more than once without an intervening
9390
** call to xShutdown().
9391
**
9392
** [[the xCreate() page cache methods]]
9393
** ^SQLite invokes the xCreate() method to construct a new cache instance.
9394
** SQLite will typically create one cache instance for each open database file,
9395
** though this is not guaranteed. ^The
9396
** first parameter, szPage, is the size in bytes of the pages that must
9397
** be allocated by the cache. ^szPage will always be a power of two. ^The
9398
** second parameter szExtra is a number of bytes of extra storage
9399
** associated with each page cache entry. ^The szExtra parameter will be
9400
** a number less than 250. SQLite will use the
9401
** extra szExtra bytes on each page to store metadata about the underlying
9402
** database page on disk. The value passed into szExtra depends
9403
** on the SQLite version, the target platform, and how SQLite was compiled.
9404
** ^The third argument to xCreate(), bPurgeable, is true if the cache being
9405
** created will be used to cache database pages of a file stored on disk, or
9406
** false if it is used for an in-memory database. The cache implementation
9407
** does not have to do anything special based upon the value of bPurgeable;
9408
** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
9409
** never invoke xUnpin() except to deliberately delete a page.
9410
** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
9411
** false will always have the "discard" flag set to true.
9412
** ^Hence, a cache created with bPurgeable set to false will
9413
** never contain any unpinned pages.
9414
**
9415
** [[the xCachesize() page cache method]]
9416
** ^(The xCachesize() method may be called at any time by SQLite to set the
9417
** suggested maximum cache-size (number of pages stored) for the cache
9418
** instance passed as the first argument. This is the value configured using
9419
** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
9420
** parameter, the implementation is not required to do anything with this
9421
** value; it is advisory only.
9422
**
9423
** [[the xPagecount() page cache methods]]
9424
** The xPagecount() method must return the number of pages currently
9425
** stored in the cache, both pinned and unpinned.
9426
**
9427
** [[the xFetch() page cache methods]]
9428
** The xFetch() method locates a page in the cache and returns a pointer to
9429
** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
9430
** The pBuf element of the returned sqlite3_pcache_page object will be a
9431
** pointer to a buffer of szPage bytes used to store the content of a
9432
** single database page. The pExtra element of sqlite3_pcache_page will be
9433
** a pointer to the szExtra bytes of extra storage that SQLite has requested
9434
** for each entry in the page cache.
9435
**
9436
** The page to be fetched is determined by the key. ^The minimum key value
9437
** is 1. After it has been retrieved using xFetch, the page is considered
9438
** to be "pinned".
9439
**
9440
** If the requested page is already in the page cache, then the page cache
9441
** implementation must return a pointer to the page buffer with its content
9442
** intact. If the requested page is not already in the cache, then the
9443
** cache implementation should use the value of the createFlag
9444
** parameter to help it determine what action to take:
9445
**
9446
** <table border=1 width=85% align=center>
9447
** <tr><th> createFlag <th> Behavior when page is not already in cache
9448
** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
9449
** <tr><td> 1 <td> Allocate a new page if it is easy and convenient to do so.
9450
** Otherwise return NULL.
9451
** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
9452
** NULL if allocating a new page is effectively impossible.
9453
** </table>
9454
**
9455
** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
9456
** will only use a createFlag of 2 after a prior call with a createFlag of 1
9457
** failed.)^ In between the xFetch() calls, SQLite may
9458
** attempt to unpin one or more cache pages by spilling the content of
9459
** pinned pages to disk and synching the operating system disk cache.
9460
**
9461
** [[the xUnpin() page cache method]]
9462
** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
9463
** as its second argument. If the third parameter, discard, is non-zero,
9464
** then the page must be evicted from the cache.
9465
** ^If the discard parameter is
9466
** zero, then the page may be discarded or retained at the discretion of the
9467
** page cache implementation. ^The page cache implementation
9468
** may choose to evict unpinned pages at any time.
9469
**
9470
** The cache must not perform any reference counting. A single
9471
** call to xUnpin() unpins the page regardless of the number of prior calls
9472
** to xFetch().
9473
**
9474
** [[the xRekey() page cache methods]]
9475
** The xRekey() method is used to change the key value associated with the
9476
** page passed as the second argument. If the cache
9477
** previously contains an entry associated with newKey, it must be
9478
** discarded. ^Any prior cache entry associated with newKey is guaranteed not
9479
** to be pinned.
9480
**
9481
** When SQLite calls the xTruncate() method, the cache must discard all
9482
** existing cache entries with page numbers (keys) greater than or equal
9483
** to the value of the iLimit parameter passed to xTruncate(). If any
9484
** of these pages are pinned, they become implicitly unpinned, meaning that
9485
** they can be safely discarded.
9486
**
9487
** [[the xDestroy() page cache method]]
9488
** ^The xDestroy() method is used to delete a cache allocated by xCreate().
9489
** All resources associated with the specified cache should be freed. ^After
9490
** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
9491
** handle invalid, and will not use it with any other sqlite3_pcache_methods2
9492
** functions.
9493
**
9494
** [[the xShrink() page cache method]]
9495
** ^SQLite invokes the xShrink() method when it wants the page cache to
9496
** free up as much of heap memory as possible. The page cache implementation
9497
** is not obligated to free any memory, but well-behaved implementations should
9498
** do their best.
9499
*/
9500
typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
9501
struct sqlite3_pcache_methods2 {
9502
int iVersion;
9503
void *pArg;
9504
int (*xInit)(void*);
9505
void (*xShutdown)(void*);
9506
sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
9507
void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9508
int (*xPagecount)(sqlite3_pcache*);
9509
sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9510
void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
9511
void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
9512
unsigned oldKey, unsigned newKey);
9513
void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9514
void (*xDestroy)(sqlite3_pcache*);
9515
void (*xShrink)(sqlite3_pcache*);
9516
};
9517
9518
/*
9519
** This is the obsolete pcache_methods object that has now been replaced
9520
** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
9521
** retained in the header file for backwards compatibility only.
9522
*/
9523
typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
9524
struct sqlite3_pcache_methods {
9525
void *pArg;
9526
int (*xInit)(void*);
9527
void (*xShutdown)(void*);
9528
sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
9529
void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9530
int (*xPagecount)(sqlite3_pcache*);
9531
void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9532
void (*xUnpin)(sqlite3_pcache*, void*, int discard);
9533
void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
9534
void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9535
void (*xDestroy)(sqlite3_pcache*);
9536
};
9537
9538
9539
/*
9540
** CAPI3REF: Online Backup Object
9541
**
9542
** The sqlite3_backup object records state information about an ongoing
9543
** online backup operation. ^The sqlite3_backup object is created by
9544
** a call to [sqlite3_backup_init()] and is destroyed by a call to
9545
** [sqlite3_backup_finish()].
9546
**
9547
** See Also: [Using the SQLite Online Backup API]
9548
*/
9549
typedef struct sqlite3_backup sqlite3_backup;
9550
9551
/*
9552
** CAPI3REF: Online Backup API.
9553
**
9554
** The backup API copies the content of one database into another.
9555
** It is useful either for creating backups of databases or
9556
** for copying in-memory databases to or from persistent files.
9557
**
9558
** See Also: [Using the SQLite Online Backup API]
9559
**
9560
** ^SQLite holds a write transaction open on the destination database file
9561
** for the duration of the backup operation.
9562
** ^The source database is read-locked only while it is being read;
9563
** it is not locked continuously for the entire backup operation.
9564
** ^Thus, the backup may be performed on a live source database without
9565
** preventing other database connections from
9566
** reading or writing to the source database while the backup is underway.
9567
**
9568
** ^(To perform a backup operation:
9569
** <ol>
9570
** <li><b>sqlite3_backup_init()</b> is called once to initialize the
9571
** backup,
9572
** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
9573
** the data between the two databases, and finally
9574
** <li><b>sqlite3_backup_finish()</b> is called to release all resources
9575
** associated with the backup operation.
9576
** </ol>)^
9577
** There should be exactly one call to sqlite3_backup_finish() for each
9578
** successful call to sqlite3_backup_init().
9579
**
9580
** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
9581
**
9582
** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
9583
** [database connection] associated with the destination database
9584
** and the database name, respectively.
9585
** ^The database name is "main" for the main database, "temp" for the
9586
** temporary database, or the name specified after the AS keyword in
9587
** an [ATTACH] statement for an attached database.
9588
** ^The S and M arguments passed to
9589
** sqlite3_backup_init(D,N,S,M) identify the [database connection]
9590
** and database name of the source database, respectively.
9591
** ^The source and destination [database connections] (parameters S and D)
9592
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
9593
** an error.
9594
**
9595
** ^A call to sqlite3_backup_init() will fail, returning NULL, if
9596
** there is already a read or read-write transaction open on the
9597
** destination database.
9598
**
9599
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
9600
** returned and an error code and error message are stored in the
9601
** destination [database connection] D.
9602
** ^The error code and message for the failed call to sqlite3_backup_init()
9603
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
9604
** [sqlite3_errmsg16()] functions.
9605
** ^A successful call to sqlite3_backup_init() returns a pointer to an
9606
** [sqlite3_backup] object.
9607
** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
9608
** sqlite3_backup_finish() functions to perform the specified backup
9609
** operation.
9610
**
9611
** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
9612
**
9613
** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
9614
** the source and destination databases specified by [sqlite3_backup] object B.
9615
** ^If N is negative, all remaining source pages are copied.
9616
** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
9617
** are still more pages to be copied, then the function returns [SQLITE_OK].
9618
** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
9619
** from source to destination, then it returns [SQLITE_DONE].
9620
** ^If an error occurs while running sqlite3_backup_step(B,N),
9621
** then an [error code] is returned. ^As well as [SQLITE_OK] and
9622
** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
9623
** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
9624
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
9625
**
9626
** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
9627
** <ol>
9628
** <li> the destination database was opened read-only, or
9629
** <li> the destination database is using write-ahead-log journaling
9630
** and the destination and source page sizes differ, or
9631
** <li> the destination database is an in-memory database and the
9632
** destination and source page sizes differ.
9633
** </ol>)^
9634
**
9635
** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
9636
** the [sqlite3_busy_handler | busy-handler function]
9637
** is invoked (if one is specified). ^If the
9638
** busy-handler returns non-zero before the lock is available, then
9639
** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
9640
** sqlite3_backup_step() can be retried later. ^If the source
9641
** [database connection]
9642
** is being used to write to the source database when sqlite3_backup_step()
9643
** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
9644
** case the call to sqlite3_backup_step() can be retried later on. ^(If
9645
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
9646
** [SQLITE_READONLY] is returned, then
9647
** there is no point in retrying the call to sqlite3_backup_step(). These
9648
** errors are considered fatal.)^ The application must accept
9649
** that the backup operation has failed and pass the backup operation handle
9650
** to the sqlite3_backup_finish() to release associated resources.
9651
**
9652
** ^The first call to sqlite3_backup_step() obtains an exclusive lock
9653
** on the destination file. ^The exclusive lock is not released until either
9654
** sqlite3_backup_finish() is called or the backup operation is complete
9655
** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
9656
** sqlite3_backup_step() obtains a [shared lock] on the source database that
9657
** lasts for the duration of the sqlite3_backup_step() call.
9658
** ^Because the source database is not locked between calls to
9659
** sqlite3_backup_step(), the source database may be modified mid-way
9660
** through the backup process. ^If the source database is modified by an
9661
** external process or via a database connection other than the one being
9662
** used by the backup operation, then the backup will be automatically
9663
** restarted by the next call to sqlite3_backup_step(). ^If the source
9664
** database is modified by using the same database connection as is used
9665
** by the backup operation, then the backup database is automatically
9666
** updated at the same time.
9667
**
9668
** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
9669
**
9670
** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
9671
** application wishes to abandon the backup operation, the application
9672
** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
9673
** ^The sqlite3_backup_finish() interfaces releases all
9674
** resources associated with the [sqlite3_backup] object.
9675
** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
9676
** active write-transaction on the destination database is rolled back.
9677
** The [sqlite3_backup] object is invalid
9678
** and may not be used following a call to sqlite3_backup_finish().
9679
**
9680
** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
9681
** sqlite3_backup_step() errors occurred, regardless of whether or not
9682
** sqlite3_backup_step() completed.
9683
** ^If an out-of-memory condition or IO error occurred during any prior
9684
** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
9685
** sqlite3_backup_finish() returns the corresponding [error code].
9686
**
9687
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
9688
** is not a permanent error and does not affect the return value of
9689
** sqlite3_backup_finish().
9690
**
9691
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
9692
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
9693
**
9694
** ^The sqlite3_backup_remaining() routine returns the number of pages still
9695
** to be backed up at the conclusion of the most recent sqlite3_backup_step().
9696
** ^The sqlite3_backup_pagecount() routine returns the total number of pages
9697
** in the source database at the conclusion of the most recent
9698
** sqlite3_backup_step().
9699
** ^(The values returned by these functions are only updated by
9700
** sqlite3_backup_step(). If the source database is modified in a way that
9701
** changes the size of the source database or the number of pages remaining,
9702
** those changes are not reflected in the output of sqlite3_backup_pagecount()
9703
** and sqlite3_backup_remaining() until after the next
9704
** sqlite3_backup_step().)^
9705
**
9706
** <b>Concurrent Usage of Database Handles</b>
9707
**
9708
** ^The source [database connection] may be used by the application for other
9709
** purposes while a backup operation is underway or being initialized.
9710
** ^If SQLite is compiled and configured to support threadsafe database
9711
** connections, then the source database connection may be used concurrently
9712
** from within other threads.
9713
**
9714
** However, the application must guarantee that the destination
9715
** [database connection] is not passed to any other API (by any thread) after
9716
** sqlite3_backup_init() is called and before the corresponding call to
9717
** sqlite3_backup_finish(). SQLite does not currently check to see
9718
** if the application incorrectly accesses the destination [database connection]
9719
** and so no error code is reported, but the operations may malfunction
9720
** nevertheless. Use of the destination database connection while a
9721
** backup is in progress might also cause a mutex deadlock.
9722
**
9723
** If running in [shared cache mode], the application must
9724
** guarantee that the shared cache used by the destination database
9725
** is not accessed while the backup is running. In practice this means
9726
** that the application must guarantee that the disk file being
9727
** backed up to is not accessed by any connection within the process,
9728
** not just the specific connection that was passed to sqlite3_backup_init().
9729
**
9730
** The [sqlite3_backup] object itself is partially threadsafe. Multiple
9731
** threads may safely make multiple concurrent calls to sqlite3_backup_step().
9732
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
9733
** APIs are not strictly speaking threadsafe. If they are invoked at the
9734
** same time as another thread is invoking sqlite3_backup_step() it is
9735
** possible that they return invalid values.
9736
**
9737
** <b>Alternatives To Using The Backup API</b>
9738
**
9739
** Other techniques for safely creating a consistent backup of an SQLite
9740
** database include:
9741
**
9742
** <ul>
9743
** <li> The [VACUUM INTO] command.
9744
** <li> The [sqlite3_rsync] utility program.
9745
** </ul>
9746
*/
9747
SQLITE_API sqlite3_backup *sqlite3_backup_init(
9748
sqlite3 *pDest, /* Destination database handle */
9749
const char *zDestName, /* Destination database name */
9750
sqlite3 *pSource, /* Source database handle */
9751
const char *zSourceName /* Source database name */
9752
);
9753
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
9754
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
9755
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
9756
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
9757
9758
/*
9759
** CAPI3REF: Unlock Notification
9760
** METHOD: sqlite3
9761
**
9762
** ^When running in shared-cache mode, a database operation may fail with
9763
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
9764
** individual tables within the shared-cache cannot be obtained. See
9765
** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
9766
** ^This API may be used to register a callback that SQLite will invoke
9767
** when the connection currently holding the required lock relinquishes it.
9768
** ^This API is only available if the library was compiled with the
9769
** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
9770
**
9771
** See Also: [Using the SQLite Unlock Notification Feature].
9772
**
9773
** ^Shared-cache locks are released when a database connection concludes
9774
** its current transaction, either by committing it or rolling it back.
9775
**
9776
** ^When a connection (known as the blocked connection) fails to obtain a
9777
** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
9778
** identity of the database connection (the blocking connection) that
9779
** has locked the required resource is stored internally. ^After an
9780
** application receives an SQLITE_LOCKED error, it may call the
9781
** sqlite3_unlock_notify() method with the blocked connection handle as
9782
** the first argument to register for a callback that will be invoked
9783
** when the blocking connection's current transaction is concluded. ^The
9784
** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
9785
** call that concludes the blocking connection's transaction.
9786
**
9787
** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
9788
** there is a chance that the blocking connection will have already
9789
** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
9790
** If this happens, then the specified callback is invoked immediately,
9791
** from within the call to sqlite3_unlock_notify().)^
9792
**
9793
** ^If the blocked connection is attempting to obtain a write-lock on a
9794
** shared-cache table, and more than one other connection currently holds
9795
** a read-lock on the same table, then SQLite arbitrarily selects one of
9796
** the other connections to use as the blocking connection.
9797
**
9798
** ^(There may be at most one unlock-notify callback registered by a
9799
** blocked connection. If sqlite3_unlock_notify() is called when the
9800
** blocked connection already has a registered unlock-notify callback,
9801
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
9802
** called with a NULL pointer as its second argument, then any existing
9803
** unlock-notify callback is canceled. ^The blocked connection's
9804
** unlock-notify callback may also be canceled by closing the blocked
9805
** connection using [sqlite3_close()].
9806
**
9807
** The unlock-notify callback is not reentrant. If an application invokes
9808
** any sqlite3_xxx API functions from within an unlock-notify callback, a
9809
** crash or deadlock may be the result.
9810
**
9811
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
9812
** returns SQLITE_OK.
9813
**
9814
** <b>Callback Invocation Details</b>
9815
**
9816
** When an unlock-notify callback is registered, the application provides a
9817
** single void* pointer that is passed to the callback when it is invoked.
9818
** However, the signature of the callback function allows SQLite to pass
9819
** it an array of void* context pointers. The first argument passed to
9820
** an unlock-notify callback is a pointer to an array of void* pointers,
9821
** and the second is the number of entries in the array.
9822
**
9823
** When a blocking connection's transaction is concluded, there may be
9824
** more than one blocked connection that has registered for an unlock-notify
9825
** callback. ^If two or more such blocked connections have specified the
9826
** same callback function, then instead of invoking the callback function
9827
** multiple times, it is invoked once with the set of void* context pointers
9828
** specified by the blocked connections bundled together into an array.
9829
** This gives the application an opportunity to prioritize any actions
9830
** related to the set of unblocked database connections.
9831
**
9832
** <b>Deadlock Detection</b>
9833
**
9834
** Assuming that after registering for an unlock-notify callback a
9835
** database waits for the callback to be issued before taking any further
9836
** action (a reasonable assumption), then using this API may cause the
9837
** application to deadlock. For example, if connection X is waiting for
9838
** connection Y's transaction to be concluded, and similarly connection
9839
** Y is waiting on connection X's transaction, then neither connection
9840
** will proceed and the system may remain deadlocked indefinitely.
9841
**
9842
** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
9843
** detection. ^If a given call to sqlite3_unlock_notify() would put the
9844
** system in a deadlocked state, then SQLITE_LOCKED is returned and no
9845
** unlock-notify callback is registered. The system is said to be in
9846
** a deadlocked state if connection A has registered for an unlock-notify
9847
** callback on the conclusion of connection B's transaction, and connection
9848
** B has itself registered for an unlock-notify callback when connection
9849
** A's transaction is concluded. ^Indirect deadlock is also detected, so
9850
** the system is also considered to be deadlocked if connection B has
9851
** registered for an unlock-notify callback on the conclusion of connection
9852
** C's transaction, where connection C is waiting on connection A. ^Any
9853
** number of levels of indirection are allowed.
9854
**
9855
** <b>The "DROP TABLE" Exception</b>
9856
**
9857
** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
9858
** always appropriate to call sqlite3_unlock_notify(). There is however,
9859
** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
9860
** SQLite checks if there are any currently executing SELECT statements
9861
** that belong to the same connection. If there are, SQLITE_LOCKED is
9862
** returned. In this case there is no "blocking connection", so invoking
9863
** sqlite3_unlock_notify() results in the unlock-notify callback being
9864
** invoked immediately. If the application then re-attempts the "DROP TABLE"
9865
** or "DROP INDEX" query, an infinite loop might be the result.
9866
**
9867
** One way around this problem is to check the extended error code returned
9868
** by an sqlite3_step() call. ^(If there is a blocking connection, then the
9869
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
9870
** the special "DROP TABLE/INDEX" case, the extended error code is just
9871
** SQLITE_LOCKED.)^
9872
*/
9873
SQLITE_API int sqlite3_unlock_notify(
9874
sqlite3 *pBlocked, /* Waiting connection */
9875
void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
9876
void *pNotifyArg /* Argument to pass to xNotify */
9877
);
9878
9879
9880
/*
9881
** CAPI3REF: String Comparison
9882
**
9883
** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
9884
** and extensions to compare the contents of two buffers containing UTF-8
9885
** strings in a case-independent fashion, using the same definition of "case
9886
** independence" that SQLite uses internally when comparing identifiers.
9887
*/
9888
SQLITE_API int sqlite3_stricmp(const char *, const char *);
9889
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
9890
9891
/*
9892
** CAPI3REF: String Globbing
9893
*
9894
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
9895
** string X matches the [GLOB] pattern P.
9896
** ^The definition of [GLOB] pattern matching used in
9897
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
9898
** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function
9899
** is case sensitive.
9900
**
9901
** Note that this routine returns zero on a match and non-zero if the strings
9902
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9903
**
9904
** See also: [sqlite3_strlike()].
9905
*/
9906
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
9907
9908
/*
9909
** CAPI3REF: String LIKE Matching
9910
*
9911
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
9912
** string X matches the [LIKE] pattern P with escape character E.
9913
** ^The definition of [LIKE] pattern matching used in
9914
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
9915
** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without
9916
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
9917
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
9918
** insensitive - equivalent upper and lower case ASCII characters match
9919
** one another.
9920
**
9921
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
9922
** only ASCII characters are case folded.
9923
**
9924
** Note that this routine returns zero on a match and non-zero if the strings
9925
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9926
**
9927
** See also: [sqlite3_strglob()].
9928
*/
9929
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
9930
9931
/*
9932
** CAPI3REF: Error Logging Interface
9933
**
9934
** ^The [sqlite3_log()] interface writes a message into the [error log]
9935
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
9936
** ^If logging is enabled, the zFormat string and subsequent arguments are
9937
** used with [sqlite3_snprintf()] to generate the final output string.
9938
**
9939
** The sqlite3_log() interface is intended for use by extensions such as
9940
** virtual tables, collating functions, and SQL functions. While there is
9941
** nothing to prevent an application from calling sqlite3_log(), doing so
9942
** is considered bad form.
9943
**
9944
** The zFormat string must not be NULL.
9945
**
9946
** To avoid deadlocks and other threading problems, the sqlite3_log() routine
9947
** will not use dynamically allocated memory. The log message is stored in
9948
** a fixed-length buffer on the stack. If the log message is longer than
9949
** a few hundred characters, it will be truncated to the length of the
9950
** buffer.
9951
*/
9952
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
9953
9954
/*
9955
** CAPI3REF: Write-Ahead Log Commit Hook
9956
** METHOD: sqlite3
9957
**
9958
** ^The [sqlite3_wal_hook()] function is used to register a callback that
9959
** is invoked each time data is committed to a database in wal mode.
9960
**
9961
** ^(The callback is invoked by SQLite after the commit has taken place and
9962
** the associated write-lock on the database released)^, so the implementation
9963
** may read, write or [checkpoint] the database as required.
9964
**
9965
** ^The first parameter passed to the callback function when it is invoked
9966
** is a copy of the third parameter passed to sqlite3_wal_hook() when
9967
** registering the callback. ^The second is a copy of the database handle.
9968
** ^The third parameter is the name of the database that was written to -
9969
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
9970
** is the number of pages currently in the write-ahead log file,
9971
** including those that were just committed.
9972
**
9973
** ^The callback function should normally return [SQLITE_OK]. ^If an error
9974
** code is returned, that error will propagate back up through the
9975
** SQLite code base to cause the statement that provoked the callback
9976
** to report an error, though the commit will have still occurred. If the
9977
** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
9978
** that does not correspond to any valid SQLite error code, the results
9979
** are undefined.
9980
**
9981
** ^A single database handle may have at most a single write-ahead log
9982
** callback registered at one time. ^Calling [sqlite3_wal_hook()]
9983
** replaces the default behavior or previously registered write-ahead
9984
** log callback.
9985
**
9986
** ^The return value is a copy of the third parameter from the
9987
** previous call, if any, or 0.
9988
**
9989
** ^The [sqlite3_wal_autocheckpoint()] interface and the
9990
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and
9991
** will overwrite any prior [sqlite3_wal_hook()] settings.
9992
**
9993
** ^If a write-ahead log callback is set using this function then
9994
** [sqlite3_wal_checkpoint_v2()] or [PRAGMA wal_checkpoint]
9995
** should be invoked periodically to keep the write-ahead log file
9996
** from growing without bound.
9997
**
9998
** ^Passing a NULL pointer for the callback disables automatic
9999
** checkpointing entirely. To re-enable the default behavior, call
10000
** sqlite3_wal_autocheckpoint(db,1000) or use [PRAGMA wal_checkpoint].
10001
*/
10002
SQLITE_API void *sqlite3_wal_hook(
10003
sqlite3*,
10004
int(*)(void *,sqlite3*,const char*,int),
10005
void*
10006
);
10007
10008
/*
10009
** CAPI3REF: Configure an auto-checkpoint
10010
** METHOD: sqlite3
10011
**
10012
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
10013
** [sqlite3_wal_hook()] that causes any database on [database connection] D
10014
** to automatically [checkpoint]
10015
** after committing a transaction if there are N or
10016
** more frames in the [write-ahead log] file. ^Passing zero or
10017
** a negative value as the N parameter disables automatic
10018
** checkpoints entirely.
10019
**
10020
** ^The callback registered by this function replaces any existing callback
10021
** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
10022
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
10023
** configured by this function.
10024
**
10025
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
10026
** from SQL.
10027
**
10028
** ^Checkpoints initiated by this mechanism are
10029
** [sqlite3_wal_checkpoint_v2|PASSIVE].
10030
**
10031
** ^Every new [database connection] defaults to having the auto-checkpoint
10032
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
10033
** pages.
10034
**
10035
** ^The use of this interface is only necessary if the default setting
10036
** is found to be suboptimal for a particular application.
10037
*/
10038
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
10039
10040
/*
10041
** CAPI3REF: Checkpoint a database
10042
** METHOD: sqlite3
10043
**
10044
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
10045
** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
10046
**
10047
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
10048
** [write-ahead log] for database X on [database connection] D to be
10049
** transferred into the database file and for the write-ahead log to
10050
** be reset. See the [checkpointing] documentation for addition
10051
** information.
10052
**
10053
** This interface used to be the only way to cause a checkpoint to
10054
** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
10055
** interface was added. This interface is retained for backwards
10056
** compatibility and as a convenience for applications that need to manually
10057
** start a callback but which do not need the full power (and corresponding
10058
** complication) of [sqlite3_wal_checkpoint_v2()].
10059
*/
10060
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
10061
10062
/*
10063
** CAPI3REF: Checkpoint a database
10064
** METHOD: sqlite3
10065
**
10066
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
10067
** operation on database X of [database connection] D in mode M. Status
10068
** information is written back into integers pointed to by L and C.)^
10069
** ^(The M parameter must be a valid [checkpoint mode]:)^
10070
**
10071
** <dl>
10072
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
10073
** ^Checkpoint as many frames as possible without waiting for any database
10074
** readers or writers to finish, then sync the database file if all frames
10075
** in the log were checkpointed. ^The [busy-handler callback]
10076
** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
10077
** ^On the other hand, passive mode might leave the checkpoint unfinished
10078
** if there are concurrent readers or writers.
10079
**
10080
** <dt>SQLITE_CHECKPOINT_FULL<dd>
10081
** ^This mode blocks (it invokes the
10082
** [sqlite3_busy_handler|busy-handler callback]) until there is no
10083
** database writer and all readers are reading from the most recent database
10084
** snapshot. ^It then checkpoints all frames in the log file and syncs the
10085
** database file. ^This mode blocks new database writers while it is pending,
10086
** but new database readers are allowed to continue unimpeded.
10087
**
10088
** <dt>SQLITE_CHECKPOINT_RESTART<dd>
10089
** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
10090
** that after checkpointing the log file it blocks (calls the
10091
** [busy-handler callback])
10092
** until all readers are reading from the database file only. ^This ensures
10093
** that the next writer will restart the log file from the beginning.
10094
** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
10095
** database writer attempts while it is pending, but does not impede readers.
10096
**
10097
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
10098
** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
10099
** addition that it also truncates the log file to zero bytes just prior
10100
** to a successful return.
10101
**
10102
** <dt>SQLITE_CHECKPOINT_NOOP<dd>
10103
** ^This mode always checkpoints zero frames. The only reason to invoke
10104
** a NOOP checkpoint is to access the values returned by
10105
** sqlite3_wal_checkpoint_v2() via output parameters *pnLog and *pnCkpt.
10106
** </dl>
10107
**
10108
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
10109
** the log file or to -1 if the checkpoint could not run because
10110
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
10111
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
10112
** log file (including any that were already checkpointed before the function
10113
** was called) or to -1 if the checkpoint could not run due to an error or
10114
** because the database is not in WAL mode. ^Note that upon successful
10115
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
10116
** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
10117
**
10118
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
10119
** any other process is running a checkpoint operation at the same time, the
10120
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
10121
** busy-handler configured, it will not be invoked in this case.
10122
**
10123
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
10124
** exclusive "writer" lock on the database file. ^If the writer lock cannot be
10125
** obtained immediately, and a busy-handler is configured, it is invoked and
10126
** the writer lock retried until either the busy-handler returns 0 or the lock
10127
** is successfully obtained. ^The busy-handler is also invoked while waiting for
10128
** database readers as described above. ^If the busy-handler returns 0 before
10129
** the writer lock is obtained or while waiting for database readers, the
10130
** checkpoint operation proceeds from that point in the same way as
10131
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
10132
** without blocking any further. ^SQLITE_BUSY is returned in this case.
10133
**
10134
** ^If parameter zDb is NULL or points to a zero length string, then the
10135
** specified operation is attempted on all WAL databases [attached] to
10136
** [database connection] db. In this case the
10137
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
10138
** an SQLITE_BUSY error is encountered when processing one or more of the
10139
** attached WAL databases, the operation is still attempted on any remaining
10140
** attached databases and SQLITE_BUSY is returned at the end. ^If any other
10141
** error occurs while processing an attached database, processing is abandoned
10142
** and the error code is returned to the caller immediately. ^If no error
10143
** (SQLITE_BUSY or otherwise) is encountered while processing the attached
10144
** databases, SQLITE_OK is returned.
10145
**
10146
** ^If database zDb is the name of an attached database that is not in WAL
10147
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
10148
** zDb is not NULL (or a zero length string) and is not the name of any
10149
** attached database, SQLITE_ERROR is returned to the caller.
10150
**
10151
** ^Unless it returns SQLITE_MISUSE,
10152
** the sqlite3_wal_checkpoint_v2() interface
10153
** sets the error information that is queried by
10154
** [sqlite3_errcode()] and [sqlite3_errmsg()].
10155
**
10156
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
10157
** from SQL.
10158
*/
10159
SQLITE_API int sqlite3_wal_checkpoint_v2(
10160
sqlite3 *db, /* Database handle */
10161
const char *zDb, /* Name of attached database (or NULL) */
10162
int eMode, /* SQLITE_CHECKPOINT_* value */
10163
int *pnLog, /* OUT: Size of WAL log in frames */
10164
int *pnCkpt /* OUT: Total number of frames checkpointed */
10165
);
10166
10167
/*
10168
** CAPI3REF: Checkpoint Mode Values
10169
** KEYWORDS: {checkpoint mode}
10170
**
10171
** These constants define all valid values for the "checkpoint mode" passed
10172
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
10173
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
10174
** meaning of each of these checkpoint modes.
10175
*/
10176
#define SQLITE_CHECKPOINT_NOOP -1 /* Do no work at all */
10177
#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */
10178
#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */
10179
#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */
10180
#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */
10181
10182
/*
10183
** CAPI3REF: Virtual Table Interface Configuration
10184
**
10185
** This function may be called by either the [xConnect] or [xCreate] method
10186
** of a [virtual table] implementation to configure
10187
** various facets of the virtual table interface.
10188
**
10189
** If this interface is invoked outside the context of an xConnect or
10190
** xCreate virtual table method then the behavior is undefined.
10191
**
10192
** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
10193
** [database connection] in which the virtual table is being created and
10194
** which is passed in as the first argument to the [xConnect] or [xCreate]
10195
** method that is invoking sqlite3_vtab_config(). The C parameter is one
10196
** of the [virtual table configuration options]. The presence and meaning
10197
** of parameters after C depend on which [virtual table configuration option]
10198
** is used.
10199
*/
10200
SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
10201
10202
/*
10203
** CAPI3REF: Virtual Table Configuration Options
10204
** KEYWORDS: {virtual table configuration options}
10205
** KEYWORDS: {virtual table configuration option}
10206
**
10207
** These macros define the various options to the
10208
** [sqlite3_vtab_config()] interface that [virtual table] implementations
10209
** can use to customize and optimize their behavior.
10210
**
10211
** <dl>
10212
** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
10213
** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
10214
** <dd>Calls of the form
10215
** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
10216
** where X is an integer. If X is zero, then the [virtual table] whose
10217
** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
10218
** support constraints. In this configuration (which is the default) if
10219
** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
10220
** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
10221
** specified as part of the user's SQL statement, regardless of the actual
10222
** ON CONFLICT mode specified.
10223
**
10224
** If X is non-zero, then the virtual table implementation guarantees
10225
** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
10226
** any modifications to internal or persistent data structures have been made.
10227
** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
10228
** is able to roll back a statement or database transaction, and abandon
10229
** or continue processing the current SQL statement as appropriate.
10230
** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
10231
** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
10232
** had been ABORT.
10233
**
10234
** Virtual table implementations that are required to handle OR REPLACE
10235
** must do so within the [xUpdate] method. If a call to the
10236
** [sqlite3_vtab_on_conflict()] function indicates that the current ON
10237
** CONFLICT policy is REPLACE, the virtual table implementation should
10238
** silently replace the appropriate rows within the xUpdate callback and
10239
** return SQLITE_OK. Or, if this is not possible, it may return
10240
** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
10241
** constraint handling.
10242
** </dd>
10243
**
10244
** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
10245
** <dd>Calls of the form
10246
** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
10247
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
10248
** prohibits that virtual table from being used from within triggers and
10249
** views.
10250
** </dd>
10251
**
10252
** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
10253
** <dd>Calls of the form
10254
** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
10255
** [xConnect] or [xCreate] methods of a [virtual table] implementation
10256
** identify that virtual table as being safe to use from within triggers
10257
** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
10258
** virtual table can do no serious harm even if it is controlled by a
10259
** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
10260
** flag unless absolutely necessary.
10261
** </dd>
10262
**
10263
** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt>
10264
** <dd>Calls of the form
10265
** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the
10266
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
10267
** instruct the query planner to begin at least a read transaction on
10268
** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the
10269
** virtual table is used.
10270
** </dd>
10271
** </dl>
10272
*/
10273
#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
10274
#define SQLITE_VTAB_INNOCUOUS 2
10275
#define SQLITE_VTAB_DIRECTONLY 3
10276
#define SQLITE_VTAB_USES_ALL_SCHEMAS 4
10277
10278
/*
10279
** CAPI3REF: Determine The Virtual Table Conflict Policy
10280
**
10281
** This function may only be called from within a call to the [xUpdate] method
10282
** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
10283
** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
10284
** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
10285
** of the SQL statement that triggered the call to the [xUpdate] method of the
10286
** [virtual table].
10287
*/
10288
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
10289
10290
/*
10291
** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
10292
**
10293
** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
10294
** method of a [virtual table], then it might return true if the
10295
** column is being fetched as part of an UPDATE operation during which the
10296
** column value will not change. The virtual table implementation can use
10297
** this hint as permission to substitute a return value that is less
10298
** expensive to compute and that the corresponding
10299
** [xUpdate] method understands as a "no-change" value.
10300
**
10301
** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
10302
** the column is not changed by the UPDATE statement, then the xColumn
10303
** method can optionally return without setting a result, without calling
10304
** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
10305
** In that case, [sqlite3_value_nochange(X)] will return true for the
10306
** same column in the [xUpdate] method.
10307
**
10308
** The sqlite3_vtab_nochange() routine is an optimization. Virtual table
10309
** implementations should continue to give a correct answer even if the
10310
** sqlite3_vtab_nochange() interface were to always return false. In the
10311
** current implementation, the sqlite3_vtab_nochange() interface does always
10312
** returns false for the enhanced [UPDATE FROM] statement.
10313
*/
10314
SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
10315
10316
/*
10317
** CAPI3REF: Determine The Collation For a Virtual Table Constraint
10318
** METHOD: sqlite3_index_info
10319
**
10320
** This function may only be called from within a call to the [xBestIndex]
10321
** method of a [virtual table]. This function returns a pointer to a string
10322
** that is the name of the appropriate collation sequence to use for text
10323
** comparisons on the constraint identified by its arguments.
10324
**
10325
** The first argument must be the pointer to the [sqlite3_index_info] object
10326
** that is the first parameter to the xBestIndex() method. The second argument
10327
** must be an index into the aConstraint[] array belonging to the
10328
** sqlite3_index_info structure passed to xBestIndex.
10329
**
10330
** Important:
10331
** The first parameter must be the same pointer that is passed into the
10332
** xBestMethod() method. The first parameter may not be a pointer to a
10333
** different [sqlite3_index_info] object, even an exact copy.
10334
**
10335
** The return value is computed as follows:
10336
**
10337
** <ol>
10338
** <li><p> If the constraint comes from a WHERE clause expression that contains
10339
** a [COLLATE operator], then the name of the collation specified by
10340
** that COLLATE operator is returned.
10341
** <li><p> If there is no COLLATE operator, but the column that is the subject
10342
** of the constraint specifies an alternative collating sequence via
10343
** a [COLLATE clause] on the column definition within the CREATE TABLE
10344
** statement that was passed into [sqlite3_declare_vtab()], then the
10345
** name of that alternative collating sequence is returned.
10346
** <li><p> Otherwise, "BINARY" is returned.
10347
** </ol>
10348
*/
10349
SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
10350
10351
/*
10352
** CAPI3REF: Determine if a virtual table query is DISTINCT
10353
** METHOD: sqlite3_index_info
10354
**
10355
** This API may only be used from within an [xBestIndex|xBestIndex method]
10356
** of a [virtual table] implementation. The result of calling this
10357
** interface from outside of xBestIndex() is undefined and probably harmful.
10358
**
10359
** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and
10360
** 3. The integer returned by sqlite3_vtab_distinct()
10361
** gives the virtual table additional information about how the query
10362
** planner wants the output to be ordered. As long as the virtual table
10363
** can meet the ordering requirements of the query planner, it may set
10364
** the "orderByConsumed" flag.
10365
**
10366
** <ol><li value="0"><p>
10367
** ^If the sqlite3_vtab_distinct() interface returns 0, that means
10368
** that the query planner needs the virtual table to return all rows in the
10369
** sort order defined by the "nOrderBy" and "aOrderBy" fields of the
10370
** [sqlite3_index_info] object. This is the default expectation. If the
10371
** virtual table outputs all rows in sorted order, then it is always safe for
10372
** the xBestIndex method to set the "orderByConsumed" flag, regardless of
10373
** the return value from sqlite3_vtab_distinct().
10374
** <li value="1"><p>
10375
** ^(If the sqlite3_vtab_distinct() interface returns 1, that means
10376
** that the query planner does not need the rows to be returned in sorted order
10377
** as long as all rows with the same values in all columns identified by the
10378
** "aOrderBy" field are adjacent.)^ This mode is used when the query planner
10379
** is doing a GROUP BY.
10380
** <li value="2"><p>
10381
** ^(If the sqlite3_vtab_distinct() interface returns 2, that means
10382
** that the query planner does not need the rows returned in any particular
10383
** order, as long as rows with the same values in all columns identified
10384
** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows
10385
** contain the same values for all columns identified by "colUsed", all but
10386
** one such row may optionally be omitted from the result.)^
10387
** The virtual table is not required to omit rows that are duplicates
10388
** over the "colUsed" columns, but if the virtual table can do that without
10389
** too much extra effort, it could potentially help the query to run faster.
10390
** This mode is used for a DISTINCT query.
10391
** <li value="3"><p>
10392
** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the
10393
** virtual table must return rows in the order defined by "aOrderBy" as
10394
** if the sqlite3_vtab_distinct() interface had returned 0. However if
10395
** two or more rows in the result have the same values for all columns
10396
** identified by "colUsed", then all but one such row may optionally be
10397
** omitted.)^ Like when the return value is 2, the virtual table
10398
** is not required to omit rows that are duplicates over the "colUsed"
10399
** columns, but if the virtual table can do that without
10400
** too much extra effort, it could potentially help the query to run faster.
10401
** This mode is used for queries
10402
** that have both DISTINCT and ORDER BY clauses.
10403
** </ol>
10404
**
10405
** <p>The following table summarizes the conditions under which the
10406
** virtual table is allowed to set the "orderByConsumed" flag based on
10407
** the value returned by sqlite3_vtab_distinct(). This table is a
10408
** restatement of the previous four paragraphs:
10409
**
10410
** <table border=1 cellspacing=0 cellpadding=10 width="90%">
10411
** <tr>
10412
** <td valign="top">sqlite3_vtab_distinct() return value
10413
** <td valign="top">Rows are returned in aOrderBy order
10414
** <td valign="top">Rows with the same value in all aOrderBy columns are
10415
** adjacent
10416
** <td valign="top">Duplicates over all colUsed columns may be omitted
10417
** <tr><td>0<td>yes<td>yes<td>no
10418
** <tr><td>1<td>no<td>yes<td>no
10419
** <tr><td>2<td>no<td>yes<td>yes
10420
** <tr><td>3<td>yes<td>yes<td>yes
10421
** </table>
10422
**
10423
** ^For the purposes of comparing virtual table output values to see if the
10424
** values are the same value for sorting purposes, two NULL values are
10425
** considered to be the same. In other words, the comparison operator is "IS"
10426
** (or "IS NOT DISTINCT FROM") and not "==".
10427
**
10428
** If a virtual table implementation is unable to meet the requirements
10429
** specified above, then it must not set the "orderByConsumed" flag in the
10430
** [sqlite3_index_info] object or an incorrect answer may result.
10431
**
10432
** ^A virtual table implementation is always free to return rows in any order
10433
** it wants, as long as the "orderByConsumed" flag is not set. ^When the
10434
** "orderByConsumed" flag is unset, the query planner will add extra
10435
** [bytecode] to ensure that the final results returned by the SQL query are
10436
** ordered correctly. The use of the "orderByConsumed" flag and the
10437
** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful
10438
** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed"
10439
** flag might help queries against a virtual table to run faster. Being
10440
** overly aggressive and setting the "orderByConsumed" flag when it is not
10441
** valid to do so, on the other hand, might cause SQLite to return incorrect
10442
** results.
10443
*/
10444
SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*);
10445
10446
/*
10447
** CAPI3REF: Identify and handle IN constraints in xBestIndex
10448
**
10449
** This interface may only be used from within an
10450
** [xBestIndex|xBestIndex() method] of a [virtual table] implementation.
10451
** The result of invoking this interface from any other context is
10452
** undefined and probably harmful.
10453
**
10454
** ^(A constraint on a virtual table of the form
10455
** "[IN operator|column IN (...)]" is
10456
** communicated to the xBestIndex method as a
10457
** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use
10458
** this constraint, it must set the corresponding
10459
** aConstraintUsage[].argvIndex to a positive integer. ^(Then, under
10460
** the usual mode of handling IN operators, SQLite generates [bytecode]
10461
** that invokes the [xFilter|xFilter() method] once for each value
10462
** on the right-hand side of the IN operator.)^ Thus the virtual table
10463
** only sees a single value from the right-hand side of the IN operator
10464
** at a time.
10465
**
10466
** In some cases, however, it would be advantageous for the virtual
10467
** table to see all values on the right-hand of the IN operator all at
10468
** once. The sqlite3_vtab_in() interfaces facilitates this in two ways:
10469
**
10470
** <ol>
10471
** <li><p>
10472
** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero)
10473
** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint
10474
** is an [IN operator] that can be processed all at once. ^In other words,
10475
** sqlite3_vtab_in() with -1 in the third argument is a mechanism
10476
** by which the virtual table can ask SQLite if all-at-once processing
10477
** of the IN operator is even possible.
10478
**
10479
** <li><p>
10480
** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates
10481
** to SQLite that the virtual table does or does not want to process
10482
** the IN operator all-at-once, respectively. ^Thus when the third
10483
** parameter (F) is non-negative, this interface is the mechanism by
10484
** which the virtual table tells SQLite how it wants to process the
10485
** IN operator.
10486
** </ol>
10487
**
10488
** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times
10489
** within the same xBestIndex method call. ^For any given P,N pair,
10490
** the return value from sqlite3_vtab_in(P,N,F) will always be the same
10491
** within the same xBestIndex call. ^If the interface returns true
10492
** (non-zero), that means that the constraint is an IN operator
10493
** that can be processed all-at-once. ^If the constraint is not an IN
10494
** operator or cannot be processed all-at-once, then the interface returns
10495
** false.
10496
**
10497
** ^(All-at-once processing of the IN operator is selected if both of the
10498
** following conditions are met:
10499
**
10500
** <ol>
10501
** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive
10502
** integer. This is how the virtual table tells SQLite that it wants to
10503
** use the N-th constraint.
10504
**
10505
** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was
10506
** non-negative had F>=1.
10507
** </ol>)^
10508
**
10509
** ^If either or both of the conditions above are false, then SQLite uses
10510
** the traditional one-at-a-time processing strategy for the IN constraint.
10511
** ^If both conditions are true, then the argvIndex-th parameter to the
10512
** xFilter method will be an [sqlite3_value] that appears to be NULL,
10513
** but which can be passed to [sqlite3_vtab_in_first()] and
10514
** [sqlite3_vtab_in_next()] to find all values on the right-hand side
10515
** of the IN constraint.
10516
*/
10517
SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle);
10518
10519
/*
10520
** CAPI3REF: Find all elements on the right-hand side of an IN constraint.
10521
**
10522
** These interfaces are only useful from within the
10523
** [xFilter|xFilter() method] of a [virtual table] implementation.
10524
** The result of invoking these interfaces from any other context
10525
** is undefined and probably harmful.
10526
**
10527
** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
10528
** sqlite3_vtab_in_next(X,P) should be one of the parameters to the
10529
** xFilter method which invokes these routines, and specifically
10530
** a parameter that was previously selected for all-at-once IN constraint
10531
** processing using the [sqlite3_vtab_in()] interface in the
10532
** [xBestIndex|xBestIndex method]. ^(If the X parameter is not
10533
** an xFilter argument that was selected for all-at-once IN constraint
10534
** processing, then these routines return [SQLITE_ERROR].)^
10535
**
10536
** ^(Use these routines to access all values on the right-hand side
10537
** of the IN constraint using code like the following:
10538
**
10539
** <blockquote><pre>
10540
** &nbsp; for(rc=sqlite3_vtab_in_first(pList, &pVal);
10541
** &nbsp; rc==SQLITE_OK && pVal;
10542
** &nbsp; rc=sqlite3_vtab_in_next(pList, &pVal)
10543
** &nbsp; ){
10544
** &nbsp; // do something with pVal
10545
** &nbsp; }
10546
** &nbsp; if( rc!=SQLITE_DONE ){
10547
** &nbsp; // an error has occurred
10548
** &nbsp; }
10549
** </pre></blockquote>)^
10550
**
10551
** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P)
10552
** routines return SQLITE_OK and set *P to point to the first or next value
10553
** on the RHS of the IN constraint. ^If there are no more values on the
10554
** right hand side of the IN constraint, then *P is set to NULL and these
10555
** routines return [SQLITE_DONE]. ^The return value might be
10556
** some other value, such as SQLITE_NOMEM, in the event of a malfunction.
10557
**
10558
** The *ppOut values returned by these routines are only valid until the
10559
** next call to either of these routines or until the end of the xFilter
10560
** method from which these routines were called. If the virtual table
10561
** implementation needs to retain the *ppOut values for longer, it must make
10562
** copies. The *ppOut values are [protected sqlite3_value|protected].
10563
*/
10564
SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut);
10565
SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut);
10566
10567
/*
10568
** CAPI3REF: Constraint values in xBestIndex()
10569
** METHOD: sqlite3_index_info
10570
**
10571
** This API may only be used from within the [xBestIndex|xBestIndex method]
10572
** of a [virtual table] implementation. The result of calling this interface
10573
** from outside of an xBestIndex method are undefined and probably harmful.
10574
**
10575
** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within
10576
** the [xBestIndex] method of a [virtual table] implementation, with P being
10577
** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and
10578
** J being a 0-based index into P->aConstraint[], then this routine
10579
** attempts to set *V to the value of the right-hand operand of
10580
** that constraint if the right-hand operand is known. ^If the
10581
** right-hand operand is not known, then *V is set to a NULL pointer.
10582
** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if
10583
** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V)
10584
** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th
10585
** constraint is not available. ^The sqlite3_vtab_rhs_value() interface
10586
** can return a result code other than SQLITE_OK or SQLITE_NOTFOUND if
10587
** something goes wrong.
10588
**
10589
** The sqlite3_vtab_rhs_value() interface is usually only successful if
10590
** the right-hand operand of a constraint is a literal value in the original
10591
** SQL statement. If the right-hand operand is an expression or a reference
10592
** to some other column or a [host parameter], then sqlite3_vtab_rhs_value()
10593
** will probably return [SQLITE_NOTFOUND].
10594
**
10595
** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and
10596
** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such
10597
** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^
10598
**
10599
** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value
10600
** and remains valid for the duration of the xBestIndex method call.
10601
** ^When xBestIndex returns, the sqlite3_value object returned by
10602
** sqlite3_vtab_rhs_value() is automatically deallocated.
10603
**
10604
** The "_rhs_" in the name of this routine is an abbreviation for
10605
** "Right-Hand Side".
10606
*/
10607
SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal);
10608
10609
/*
10610
** CAPI3REF: Conflict resolution modes
10611
** KEYWORDS: {conflict resolution mode}
10612
**
10613
** These constants are returned by [sqlite3_vtab_on_conflict()] to
10614
** inform a [virtual table] implementation of the [ON CONFLICT] mode
10615
** for the SQL statement being evaluated.
10616
**
10617
** Note that the [SQLITE_IGNORE] constant is also used as a potential
10618
** return value from the [sqlite3_set_authorizer()] callback and that
10619
** [SQLITE_ABORT] is also a [result code].
10620
*/
10621
#define SQLITE_ROLLBACK 1
10622
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
10623
#define SQLITE_FAIL 3
10624
/* #define SQLITE_ABORT 4 // Also an error code */
10625
#define SQLITE_REPLACE 5
10626
10627
/*
10628
** CAPI3REF: Prepared Statement Scan Status Opcodes
10629
** KEYWORDS: {scanstatus options}
10630
**
10631
** The following constants can be used for the T parameter to the
10632
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a
10633
** different metric for sqlite3_stmt_scanstatus() to return.
10634
**
10635
** When the value returned to V is a string, space to hold that string is
10636
** managed by the prepared statement S and will be automatically freed when
10637
** S is finalized.
10638
**
10639
** Not all values are available for all query elements. When a value is
10640
** not available, the output variable is set to -1 if the value is numeric,
10641
** or to NULL if it is a string (SQLITE_SCANSTAT_NAME).
10642
**
10643
** <dl>
10644
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
10645
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
10646
** set to the total number of times that the X-th loop has run.</dd>
10647
**
10648
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
10649
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
10650
** to the total number of rows examined by all iterations of the X-th loop.</dd>
10651
**
10652
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
10653
** <dd>^The "double" variable pointed to by the V parameter will be set to the
10654
** query planner's estimate for the average number of rows output from each
10655
** iteration of the X-th loop. If the query planner's estimate was accurate,
10656
** then this value will approximate the quotient NVISIT/NLOOP and the
10657
** product of this value for all prior loops with the same SELECTID will
10658
** be the NLOOP value for the current loop.</dd>
10659
**
10660
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
10661
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10662
** to a zero-terminated UTF-8 string containing the name of the index or table
10663
** used for the X-th loop.</dd>
10664
**
10665
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
10666
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10667
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
10668
** description for the X-th loop.</dd>
10669
**
10670
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt>
10671
** <dd>^The "int" variable pointed to by the V parameter will be set to the
10672
** id for the X-th query plan element. The id value is unique within the
10673
** statement. The select-id is the same value as is output in the first
10674
** column of an [EXPLAIN QUERY PLAN] query.</dd>
10675
**
10676
** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt>
10677
** <dd>The "int" variable pointed to by the V parameter will be set to the
10678
** id of the parent of the current query element, if applicable, or
10679
** to zero if the query element has no parent. This is the same value as
10680
** returned in the second column of an [EXPLAIN QUERY PLAN] query.</dd>
10681
**
10682
** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt>
10683
** <dd>The sqlite3_int64 output value is set to the number of cycles,
10684
** according to the processor time-stamp counter, that elapsed while the
10685
** query element was being processed. This value is not available for
10686
** all query elements - if it is unavailable the output variable is
10687
** set to -1.</dd>
10688
** </dl>
10689
*/
10690
#define SQLITE_SCANSTAT_NLOOP 0
10691
#define SQLITE_SCANSTAT_NVISIT 1
10692
#define SQLITE_SCANSTAT_EST 2
10693
#define SQLITE_SCANSTAT_NAME 3
10694
#define SQLITE_SCANSTAT_EXPLAIN 4
10695
#define SQLITE_SCANSTAT_SELECTID 5
10696
#define SQLITE_SCANSTAT_PARENTID 6
10697
#define SQLITE_SCANSTAT_NCYCLE 7
10698
10699
/*
10700
** CAPI3REF: Prepared Statement Scan Status
10701
** METHOD: sqlite3_stmt
10702
**
10703
** These interfaces return information about the predicted and measured
10704
** performance for pStmt. Advanced applications can use this
10705
** interface to compare the predicted and the measured performance and
10706
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
10707
**
10708
** Since this interface is expected to be rarely used, it is only
10709
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
10710
** compile-time option.
10711
**
10712
** The "iScanStatusOp" parameter determines which status information to return.
10713
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
10714
** of this interface is undefined. ^The requested measurement is written into
10715
** a variable pointed to by the "pOut" parameter.
10716
**
10717
** The "flags" parameter must be passed a mask of flags. At present only
10718
** one flag is defined - [SQLITE_SCANSTAT_COMPLEX]. If SQLITE_SCANSTAT_COMPLEX
10719
** is specified, then status information is available for all elements
10720
** of a query plan that are reported by "[EXPLAIN QUERY PLAN]" output. If
10721
** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements
10722
** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of
10723
** the EXPLAIN QUERY PLAN output) are available. Invoking API
10724
** sqlite3_stmt_scanstatus() is equivalent to calling
10725
** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.
10726
**
10727
** Parameter "idx" identifies the specific query element to retrieve statistics
10728
** for. Query elements are numbered starting from zero. A value of -1 may
10729
** retrieve statistics for the entire query. ^If idx is out of range
10730
** - less than -1 or greater than or equal to the total number of query
10731
** elements used to implement the statement - a non-zero value is returned and
10732
** the variable that pOut points to is unchanged.
10733
**
10734
** See also: [sqlite3_stmt_scanstatus_reset()] and the
10735
** [nexec and ncycle] columns of the [bytecode virtual table].
10736
*/
10737
SQLITE_API int sqlite3_stmt_scanstatus(
10738
sqlite3_stmt *pStmt, /* Prepared statement for which info desired */
10739
int idx, /* Index of loop to report on */
10740
int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */
10741
void *pOut /* Result written here */
10742
);
10743
SQLITE_API int sqlite3_stmt_scanstatus_v2(
10744
sqlite3_stmt *pStmt, /* Prepared statement for which info desired */
10745
int idx, /* Index of loop to report on */
10746
int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */
10747
int flags, /* Mask of flags defined below */
10748
void *pOut /* Result written here */
10749
);
10750
10751
/*
10752
** CAPI3REF: Prepared Statement Scan Status
10753
** KEYWORDS: {scan status flags}
10754
*/
10755
#define SQLITE_SCANSTAT_COMPLEX 0x0001
10756
10757
/*
10758
** CAPI3REF: Zero Scan-Status Counters
10759
** METHOD: sqlite3_stmt
10760
**
10761
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
10762
**
10763
** This API is only available if the library is built with pre-processor
10764
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
10765
*/
10766
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
10767
10768
/*
10769
** CAPI3REF: Flush caches to disk mid-transaction
10770
** METHOD: sqlite3
10771
**
10772
** ^If a write-transaction is open on [database connection] D when the
10773
** [sqlite3_db_cacheflush(D)] interface is invoked, any dirty
10774
** pages in the pager-cache that are not currently in use are written out
10775
** to disk. A dirty page may be in use if a database cursor created by an
10776
** active SQL statement is reading from it, or if it is page 1 of a database
10777
** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
10778
** interface flushes caches for all schemas - "main", "temp", and
10779
** any [attached] databases.
10780
**
10781
** ^If this function needs to obtain extra database locks before dirty pages
10782
** can be flushed to disk, it does so. ^If those locks cannot be obtained
10783
** immediately and there is a busy-handler callback configured, it is invoked
10784
** in the usual manner. ^If the required lock still cannot be obtained, then
10785
** the database is skipped and an attempt made to flush any dirty pages
10786
** belonging to the next (if any) database. ^If any databases are skipped
10787
** because locks cannot be obtained, but no other error occurs, this
10788
** function returns SQLITE_BUSY.
10789
**
10790
** ^If any other error occurs while flushing dirty pages to disk (for
10791
** example an IO error or out-of-memory condition), then processing is
10792
** abandoned and an SQLite [error code] is returned to the caller immediately.
10793
**
10794
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
10795
**
10796
** ^This function does not set the database handle error code or message
10797
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
10798
*/
10799
SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
10800
10801
/*
10802
** CAPI3REF: The pre-update hook.
10803
** METHOD: sqlite3
10804
**
10805
** ^These interfaces are only available if SQLite is compiled using the
10806
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
10807
**
10808
** ^The [sqlite3_preupdate_hook()] interface registers a callback function
10809
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
10810
** on a database table.
10811
** ^At most one preupdate hook may be registered at a time on a single
10812
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
10813
** the previous setting.
10814
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
10815
** with a NULL pointer as the second parameter.
10816
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
10817
** the first parameter to callbacks.
10818
**
10819
** ^The preupdate hook only fires for changes to real database tables; the
10820
** preupdate hook is not invoked for changes to [virtual tables] or to
10821
** system tables like sqlite_sequence or sqlite_stat1.
10822
**
10823
** ^The second parameter to the preupdate callback is a pointer to
10824
** the [database connection] that registered the preupdate hook.
10825
** ^The third parameter to the preupdate callback is one of the constants
10826
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
10827
** kind of update operation that is about to occur.
10828
** ^(The fourth parameter to the preupdate callback is the name of the
10829
** database within the database connection that is being modified. This
10830
** will be "main" for the main database or "temp" for TEMP tables or
10831
** the name given after the AS keyword in the [ATTACH] statement for attached
10832
** databases.)^
10833
** ^The fifth parameter to the preupdate callback is the name of the
10834
** table that is being modified.
10835
**
10836
** For an UPDATE or DELETE operation on a [rowid table], the sixth
10837
** parameter passed to the preupdate callback is the initial [rowid] of the
10838
** row being modified or deleted. For an INSERT operation on a rowid table,
10839
** or any operation on a WITHOUT ROWID table, the value of the sixth
10840
** parameter is undefined. For an INSERT or UPDATE on a rowid table the
10841
** seventh parameter is the final rowid value of the row being inserted
10842
** or updated. The value of the seventh parameter passed to the callback
10843
** function is not defined for operations on WITHOUT ROWID tables, or for
10844
** DELETE operations on rowid tables.
10845
**
10846
** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from
10847
** the previous call on the same [database connection] D, or NULL for
10848
** the first call on D.
10849
**
10850
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
10851
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
10852
** provide additional information about a preupdate event. These routines
10853
** may only be called from within a preupdate callback. Invoking any of
10854
** these routines from outside of a preupdate callback or with a
10855
** [database connection] pointer that is different from the one supplied
10856
** to the preupdate callback results in undefined and probably undesirable
10857
** behavior.
10858
**
10859
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
10860
** in the row that is being inserted, updated, or deleted.
10861
**
10862
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
10863
** a [protected sqlite3_value] that contains the value of the Nth column of
10864
** the table row before it is updated. The N parameter must be between 0
10865
** and one less than the number of columns or the behavior will be
10866
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
10867
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
10868
** behavior is undefined. The [sqlite3_value] that P points to
10869
** will be destroyed when the preupdate callback returns.
10870
**
10871
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
10872
** a [protected sqlite3_value] that contains the value of the Nth column of
10873
** the table row after it is updated. The N parameter must be between 0
10874
** and one less than the number of columns or the behavior will be
10875
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
10876
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
10877
** behavior is undefined. The [sqlite3_value] that P points to
10878
** will be destroyed when the preupdate callback returns.
10879
**
10880
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
10881
** callback was invoked as a result of a direct insert, update, or delete
10882
** operation; or 1 for inserts, updates, or deletes invoked by top-level
10883
** triggers; or 2 for changes resulting from triggers called by top-level
10884
** triggers; and so forth.
10885
**
10886
** When the [sqlite3_blob_write()] API is used to update a blob column,
10887
** the pre-update hook is invoked with SQLITE_DELETE, because
10888
** the new values are not yet available. In this case, when a
10889
** callback made with op==SQLITE_DELETE is actually a write using the
10890
** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns
10891
** the index of the column being written. In other cases, where the
10892
** pre-update hook is being invoked for some other reason, including a
10893
** regular DELETE, sqlite3_preupdate_blobwrite() returns -1.
10894
**
10895
** See also: [sqlite3_update_hook()]
10896
*/
10897
#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
10898
SQLITE_API void *sqlite3_preupdate_hook(
10899
sqlite3 *db,
10900
void(*xPreUpdate)(
10901
void *pCtx, /* Copy of third arg to preupdate_hook() */
10902
sqlite3 *db, /* Database handle */
10903
int op, /* SQLITE_UPDATE, DELETE or INSERT */
10904
char const *zDb, /* Database name */
10905
char const *zName, /* Table name */
10906
sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */
10907
sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */
10908
),
10909
void*
10910
);
10911
SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
10912
SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
10913
SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
10914
SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
10915
SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *);
10916
#endif
10917
10918
/*
10919
** CAPI3REF: Low-level system error code
10920
** METHOD: sqlite3
10921
**
10922
** ^Attempt to return the underlying operating system error code or error
10923
** number that caused the most recent I/O error or failure to open a file.
10924
** The return value is OS-dependent. For example, on unix systems, after
10925
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
10926
** called to get back the underlying "errno" that caused the problem, such
10927
** as ENOSPC, EAUTH, EISDIR, and so forth.
10928
*/
10929
SQLITE_API int sqlite3_system_errno(sqlite3*);
10930
10931
/*
10932
** CAPI3REF: Database Snapshot
10933
** KEYWORDS: {snapshot} {sqlite3_snapshot}
10934
**
10935
** An instance of the snapshot object records the state of a [WAL mode]
10936
** database for some specific point in history.
10937
**
10938
** In [WAL mode], multiple [database connections] that are open on the
10939
** same database file can each be reading a different historical version
10940
** of the database file. When a [database connection] begins a read
10941
** transaction, that connection sees an unchanging copy of the database
10942
** as it existed for the point in time when the transaction first started.
10943
** Subsequent changes to the database from other connections are not seen
10944
** by the reader until a new read transaction is started.
10945
**
10946
** The sqlite3_snapshot object records state information about an historical
10947
** version of the database file so that it is possible to later open a new read
10948
** transaction that sees that historical version of the database rather than
10949
** the most recent version.
10950
*/
10951
typedef struct sqlite3_snapshot {
10952
unsigned char hidden[48];
10953
} sqlite3_snapshot;
10954
10955
/*
10956
** CAPI3REF: Record A Database Snapshot
10957
** CONSTRUCTOR: sqlite3_snapshot
10958
**
10959
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
10960
** new [sqlite3_snapshot] object that records the current state of
10961
** schema S in database connection D. ^On success, the
10962
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
10963
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
10964
** If there is not already a read-transaction open on schema S when
10965
** this function is called, one is opened automatically.
10966
**
10967
** If a read-transaction is opened by this function, then it is guaranteed
10968
** that the returned snapshot object may not be invalidated by a database
10969
** writer or checkpointer until after the read-transaction is closed. This
10970
** is not guaranteed if a read-transaction is already open when this
10971
** function is called. In that case, any subsequent write or checkpoint
10972
** operation on the database may invalidate the returned snapshot handle,
10973
** even while the read-transaction remains open.
10974
**
10975
** The following must be true for this function to succeed. If any of
10976
** the following statements are false when sqlite3_snapshot_get() is
10977
** called, SQLITE_ERROR is returned. The final value of *P is undefined
10978
** in this case.
10979
**
10980
** <ul>
10981
** <li> The database handle must not be in [autocommit mode].
10982
**
10983
** <li> Schema S of [database connection] D must be a [WAL mode] database.
10984
**
10985
** <li> There must not be a write transaction open on schema S of database
10986
** connection D.
10987
**
10988
** <li> One or more transactions must have been written to the current wal
10989
** file since it was created on disk (by any connection). This means
10990
** that a snapshot cannot be taken on a wal mode database with no wal
10991
** file immediately after it is first opened. At least one transaction
10992
** must be written to it first.
10993
** </ul>
10994
**
10995
** This function may also return SQLITE_NOMEM. If it is called with the
10996
** database handle in autocommit mode but fails for some other reason,
10997
** whether or not a read transaction is opened on schema S is undefined.
10998
**
10999
** The [sqlite3_snapshot] object returned from a successful call to
11000
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
11001
** to avoid a memory leak.
11002
**
11003
** The [sqlite3_snapshot_get()] interface is only available when the
11004
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
11005
*/
11006
SQLITE_API int sqlite3_snapshot_get(
11007
sqlite3 *db,
11008
const char *zSchema,
11009
sqlite3_snapshot **ppSnapshot
11010
);
11011
11012
/*
11013
** CAPI3REF: Start a read transaction on an historical snapshot
11014
** METHOD: sqlite3_snapshot
11015
**
11016
** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
11017
** transaction or upgrades an existing one for schema S of
11018
** [database connection] D such that the read transaction refers to
11019
** historical [snapshot] P, rather than the most recent change to the
11020
** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
11021
** on success or an appropriate [error code] if it fails.
11022
**
11023
** ^In order to succeed, the database connection must not be in
11024
** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
11025
** is already a read transaction open on schema S, then the database handle
11026
** must have no active statements (SELECT statements that have been passed
11027
** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
11028
** SQLITE_ERROR is returned if either of these conditions is violated, or
11029
** if schema S does not exist, or if the snapshot object is invalid.
11030
**
11031
** ^A call to sqlite3_snapshot_open() will fail to open if the specified
11032
** snapshot has been overwritten by a [checkpoint]. In this case
11033
** SQLITE_ERROR_SNAPSHOT is returned.
11034
**
11035
** If there is already a read transaction open when this function is
11036
** invoked, then the same read transaction remains open (on the same
11037
** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
11038
** is returned. If another error code - for example SQLITE_PROTOCOL or an
11039
** SQLITE_IOERR error code - is returned, then the final state of the
11040
** read transaction is undefined. If SQLITE_OK is returned, then the
11041
** read transaction is now open on database snapshot P.
11042
**
11043
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
11044
** database connection D does not know that the database file for
11045
** schema S is in [WAL mode]. A database connection might not know
11046
** that the database file is in [WAL mode] if there has been no prior
11047
** I/O on that database connection, or if the database entered [WAL mode]
11048
** after the most recent I/O on the database connection.)^
11049
** (Hint: Run "[PRAGMA application_id]" against a newly opened
11050
** database connection in order to make it ready to use snapshots.)
11051
**
11052
** The [sqlite3_snapshot_open()] interface is only available when the
11053
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
11054
*/
11055
SQLITE_API int sqlite3_snapshot_open(
11056
sqlite3 *db,
11057
const char *zSchema,
11058
sqlite3_snapshot *pSnapshot
11059
);
11060
11061
/*
11062
** CAPI3REF: Destroy a snapshot
11063
** DESTRUCTOR: sqlite3_snapshot
11064
**
11065
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
11066
** The application must eventually free every [sqlite3_snapshot] object
11067
** using this routine to avoid a memory leak.
11068
**
11069
** The [sqlite3_snapshot_free()] interface is only available when the
11070
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
11071
*/
11072
SQLITE_API void sqlite3_snapshot_free(sqlite3_snapshot*);
11073
11074
/*
11075
** CAPI3REF: Compare the ages of two snapshot handles.
11076
** METHOD: sqlite3_snapshot
11077
**
11078
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
11079
** of two valid snapshot handles.
11080
**
11081
** If the two snapshot handles are not associated with the same database
11082
** file, the result of the comparison is undefined.
11083
**
11084
** Additionally, the result of the comparison is only valid if both of the
11085
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
11086
** last time the wal file was deleted. The wal file is deleted when the
11087
** database is changed back to rollback mode or when the number of database
11088
** clients drops to zero. If either snapshot handle was obtained before the
11089
** wal file was last deleted, the value returned by this function
11090
** is undefined.
11091
**
11092
** Otherwise, this API returns a negative value if P1 refers to an older
11093
** snapshot than P2, zero if the two handles refer to the same database
11094
** snapshot, and a positive value if P1 is a newer snapshot than P2.
11095
**
11096
** This interface is only available if SQLite is compiled with the
11097
** [SQLITE_ENABLE_SNAPSHOT] option.
11098
*/
11099
SQLITE_API int sqlite3_snapshot_cmp(
11100
sqlite3_snapshot *p1,
11101
sqlite3_snapshot *p2
11102
);
11103
11104
/*
11105
** CAPI3REF: Recover snapshots from a wal file
11106
** METHOD: sqlite3_snapshot
11107
**
11108
** If a [WAL file] remains on disk after all database connections close
11109
** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
11110
** or because the last process to have the database opened exited without
11111
** calling [sqlite3_close()]) and a new connection is subsequently opened
11112
** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
11113
** will only be able to open the last transaction added to the WAL file
11114
** even though the WAL file contains other valid transactions.
11115
**
11116
** This function attempts to scan the WAL file associated with database zDb
11117
** of database handle db and make all valid snapshots available to
11118
** sqlite3_snapshot_open(). It is an error if there is already a read
11119
** transaction open on the database, or if the database is not a WAL mode
11120
** database.
11121
**
11122
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
11123
**
11124
** This interface is only available if SQLite is compiled with the
11125
** [SQLITE_ENABLE_SNAPSHOT] option.
11126
*/
11127
SQLITE_API int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
11128
11129
/*
11130
** CAPI3REF: Serialize a database
11131
**
11132
** The sqlite3_serialize(D,S,P,F) interface returns a pointer to
11133
** memory that is a serialization of the S database on
11134
** [database connection] D. If S is a NULL pointer, the main database is used.
11135
** If P is not a NULL pointer, then the size of the database in bytes
11136
** is written into *P.
11137
**
11138
** For an ordinary on-disk database file, the serialization is just a
11139
** copy of the disk file. For an in-memory database or a "TEMP" database,
11140
** the serialization is the same sequence of bytes which would be written
11141
** to disk if that database were backed up to disk.
11142
**
11143
** The usual case is that sqlite3_serialize() copies the serialization of
11144
** the database into memory obtained from [sqlite3_malloc64()] and returns
11145
** a pointer to that memory. The caller is responsible for freeing the
11146
** returned value to avoid a memory leak. However, if the F argument
11147
** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
11148
** are made, and the sqlite3_serialize() function will return a pointer
11149
** to the contiguous memory representation of the database that SQLite
11150
** is currently using for that database, or NULL if no such contiguous
11151
** memory representation of the database exists. A contiguous memory
11152
** representation of the database will usually only exist if there has
11153
** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
11154
** values of D and S.
11155
** The size of the database is written into *P even if the
11156
** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
11157
** of the database exists.
11158
**
11159
** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set,
11160
** the returned buffer content will remain accessible and unchanged
11161
** until either the next write operation on the connection or when
11162
** the connection is closed, and applications must not modify the
11163
** buffer. If the bit had been clear, the returned buffer will not
11164
** be accessed by SQLite after the call.
11165
**
11166
** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
11167
** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
11168
** allocation error occurs.
11169
**
11170
** This interface is omitted if SQLite is compiled with the
11171
** [SQLITE_OMIT_DESERIALIZE] option.
11172
*/
11173
SQLITE_API unsigned char *sqlite3_serialize(
11174
sqlite3 *db, /* The database connection */
11175
const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */
11176
sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
11177
unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */
11178
);
11179
11180
/*
11181
** CAPI3REF: Flags for sqlite3_serialize
11182
**
11183
** Zero or more of the following constants can be OR-ed together for
11184
** the F argument to [sqlite3_serialize(D,S,P,F)].
11185
**
11186
** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
11187
** a pointer to contiguous in-memory database that it is currently using,
11188
** without making a copy of the database. If SQLite is not currently using
11189
** a contiguous in-memory database, then this option causes
11190
** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be
11191
** using a contiguous in-memory database if it has been initialized by a
11192
** prior call to [sqlite3_deserialize()].
11193
*/
11194
#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */
11195
11196
/*
11197
** CAPI3REF: Deserialize a database
11198
**
11199
** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
11200
** [database connection] D to disconnect from database S and then
11201
** reopen S as an in-memory database based on the serialization
11202
** contained in P. If S is a NULL pointer, the main database is
11203
** used. The serialized database P is N bytes in size. M is the size
11204
** of the buffer P, which might be larger than N. If M is larger than
11205
** N, and the SQLITE_DESERIALIZE_READONLY bit is not set in F, then
11206
** SQLite is permitted to add content to the in-memory database as
11207
** long as the total size does not exceed M bytes.
11208
**
11209
** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
11210
** invoke sqlite3_free() on the serialization buffer when the database
11211
** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
11212
** SQLite will try to increase the buffer size using sqlite3_realloc64()
11213
** if writes on the database cause it to grow larger than M bytes.
11214
**
11215
** Applications must not modify the buffer P or invalidate it before
11216
** the database connection D is closed.
11217
**
11218
** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
11219
** database is currently in a read transaction or is involved in a backup
11220
** operation.
11221
**
11222
** It is not possible to deserialize into the TEMP database. If the
11223
** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the
11224
** function returns SQLITE_ERROR.
11225
**
11226
** The deserialized database should not be in [WAL mode]. If the database
11227
** is in WAL mode, then any attempt to use the database file will result
11228
** in an [SQLITE_CANTOPEN] error. The application can set the
11229
** [file format version numbers] (bytes 18 and 19) of the input database P
11230
** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the
11231
** database file into rollback mode and work around this limitation.
11232
**
11233
** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
11234
** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
11235
** [sqlite3_free()] is invoked on argument P prior to returning.
11236
**
11237
** This interface is omitted if SQLite is compiled with the
11238
** [SQLITE_OMIT_DESERIALIZE] option.
11239
*/
11240
SQLITE_API int sqlite3_deserialize(
11241
sqlite3 *db, /* The database connection */
11242
const char *zSchema, /* Which DB to reopen with the deserialization */
11243
unsigned char *pData, /* The serialized database content */
11244
sqlite3_int64 szDb, /* Number of bytes in the deserialization */
11245
sqlite3_int64 szBuf, /* Total size of buffer pData[] */
11246
unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */
11247
);
11248
11249
/*
11250
** CAPI3REF: Flags for sqlite3_deserialize()
11251
**
11252
** The following are allowed values for the 6th argument (the F argument) to
11253
** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
11254
**
11255
** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
11256
** in the P argument is held in memory obtained from [sqlite3_malloc64()]
11257
** and that SQLite should take ownership of this memory and automatically
11258
** free it when it has finished using it. Without this flag, the caller
11259
** is responsible for freeing any dynamically allocated memory.
11260
**
11261
** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
11262
** grow the size of the database using calls to [sqlite3_realloc64()]. This
11263
** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
11264
** Without this flag, the deserialized database cannot increase in size beyond
11265
** the number of bytes specified by the M parameter.
11266
**
11267
** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
11268
** should be treated as read-only.
11269
*/
11270
#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
11271
#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */
11272
#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */
11273
11274
/*
11275
** CAPI3REF: Bind array values to the CARRAY table-valued function
11276
**
11277
** The sqlite3_carray_bind_v2(S,I,P,N,F,X,D) interface binds an array value to
11278
** parameter that is the first argument of the [carray() table-valued function].
11279
** The S parameter is a pointer to the [prepared statement] that uses the
11280
** carray() functions. I is the parameter index to be bound. I must be the
11281
** index of the parameter that is the first argument to the carray()
11282
** table-valued function. P is a pointer to the array to be bound, and N
11283
** is the number of elements in the array. The F argument is one of
11284
** constants [SQLITE_CARRAY_INT32], [SQLITE_CARRAY_INT64],
11285
** [SQLITE_CARRAY_DOUBLE], [SQLITE_CARRAY_TEXT],
11286
** or [SQLITE_CARRAY_BLOB] to indicate the datatype of the array P.
11287
**
11288
** If the X argument is not a NULL pointer or one of the special
11289
** values [SQLITE_STATIC] or [SQLITE_TRANSIENT], then SQLite will invoke
11290
** the function X with argument D when it is finished using the data in P.
11291
** The call to X(D) is a destructor for the array P. The destructor X(D)
11292
** is invoked even if the call to sqlite3_carray_bind_v2() fails. If the X
11293
** parameter is the special-case value [SQLITE_STATIC], then SQLite assumes
11294
** that the data static and the destructor is never invoked. If the X
11295
** parameter is the special-case value [SQLITE_TRANSIENT], then
11296
** sqlite3_carray_bind_v2() makes its own private copy of the data prior
11297
** to returning and never invokes the destructor X.
11298
**
11299
** The sqlite3_carray_bind() function works the same as sqlite3_carray_bind_v2()
11300
** with a D parameter set to P. In other words,
11301
** sqlite3_carray_bind(S,I,P,N,F,X) is same as
11302
** sqlite3_carray_bind_v2(S,I,P,N,F,X,P).
11303
*/
11304
SQLITE_API int sqlite3_carray_bind_v2(
11305
sqlite3_stmt *pStmt, /* Statement to be bound */
11306
int i, /* Parameter index */
11307
void *aData, /* Pointer to array data */
11308
int nData, /* Number of data elements */
11309
int mFlags, /* CARRAY flags */
11310
void (*xDel)(void*), /* Destructor for aData */
11311
void *pDel /* Optional argument to xDel() */
11312
);
11313
SQLITE_API int sqlite3_carray_bind(
11314
sqlite3_stmt *pStmt, /* Statement to be bound */
11315
int i, /* Parameter index */
11316
void *aData, /* Pointer to array data */
11317
int nData, /* Number of data elements */
11318
int mFlags, /* CARRAY flags */
11319
void (*xDel)(void*) /* Destructor for aData */
11320
);
11321
11322
/*
11323
** CAPI3REF: Datatypes for the CARRAY table-valued function
11324
**
11325
** The fifth argument to the [sqlite3_carray_bind()] interface musts be
11326
** one of the following constants, to specify the datatype of the array
11327
** that is being bound into the [carray table-valued function].
11328
*/
11329
#define SQLITE_CARRAY_INT32 0 /* Data is 32-bit signed integers */
11330
#define SQLITE_CARRAY_INT64 1 /* Data is 64-bit signed integers */
11331
#define SQLITE_CARRAY_DOUBLE 2 /* Data is doubles */
11332
#define SQLITE_CARRAY_TEXT 3 /* Data is char* */
11333
#define SQLITE_CARRAY_BLOB 4 /* Data is struct iovec */
11334
11335
/*
11336
** Versions of the above #defines that omit the initial SQLITE_, for
11337
** legacy compatibility.
11338
*/
11339
#define CARRAY_INT32 0 /* Data is 32-bit signed integers */
11340
#define CARRAY_INT64 1 /* Data is 64-bit signed integers */
11341
#define CARRAY_DOUBLE 2 /* Data is doubles */
11342
#define CARRAY_TEXT 3 /* Data is char* */
11343
#define CARRAY_BLOB 4 /* Data is struct iovec */
11344
11345
/*
11346
** Undo the hack that converts floating point types to integer for
11347
** builds on processors without floating point support.
11348
*/
11349
#ifdef SQLITE_OMIT_FLOATING_POINT
11350
# undef double
11351
#endif
11352
11353
#if defined(__wasi__)
11354
# undef SQLITE_WASI
11355
# define SQLITE_WASI 1
11356
# ifndef SQLITE_OMIT_LOAD_EXTENSION
11357
# define SQLITE_OMIT_LOAD_EXTENSION
11358
# endif
11359
# ifndef SQLITE_THREADSAFE
11360
# define SQLITE_THREADSAFE 0
11361
# endif
11362
#endif
11363
11364
#ifdef __cplusplus
11365
} /* End of the 'extern "C"' block */
11366
#endif
11367
/* #endif for SQLITE3_H will be added by mksqlite3.tcl */
11368
11369
/******** Begin file sqlite3rtree.h *********/
11370
/*
11371
** 2010 August 30
11372
**
11373
** The author disclaims copyright to this source code. In place of
11374
** a legal notice, here is a blessing:
11375
**
11376
** May you do good and not evil.
11377
** May you find forgiveness for yourself and forgive others.
11378
** May you share freely, never taking more than you give.
11379
**
11380
*************************************************************************
11381
*/
11382
11383
#ifndef _SQLITE3RTREE_H_
11384
#define _SQLITE3RTREE_H_
11385
11386
11387
#ifdef __cplusplus
11388
extern "C" {
11389
#endif
11390
11391
typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
11392
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
11393
11394
/* The double-precision datatype used by RTree depends on the
11395
** SQLITE_RTREE_INT_ONLY compile-time option.
11396
*/
11397
#ifdef SQLITE_RTREE_INT_ONLY
11398
typedef sqlite3_int64 sqlite3_rtree_dbl;
11399
#else
11400
typedef double sqlite3_rtree_dbl;
11401
#endif
11402
11403
/*
11404
** Register a geometry callback named zGeom that can be used as part of an
11405
** R-Tree geometry query as follows:
11406
**
11407
** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
11408
*/
11409
SQLITE_API int sqlite3_rtree_geometry_callback(
11410
sqlite3 *db,
11411
const char *zGeom,
11412
int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
11413
void *pContext
11414
);
11415
11416
11417
/*
11418
** A pointer to a structure of the following type is passed as the first
11419
** argument to callbacks registered using rtree_geometry_callback().
11420
*/
11421
struct sqlite3_rtree_geometry {
11422
void *pContext; /* Copy of pContext passed to s_r_g_c() */
11423
int nParam; /* Size of array aParam[] */
11424
sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */
11425
void *pUser; /* Callback implementation user data */
11426
void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
11427
};
11428
11429
/*
11430
** Register a 2nd-generation geometry callback named zScore that can be
11431
** used as part of an R-Tree geometry query as follows:
11432
**
11433
** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
11434
*/
11435
SQLITE_API int sqlite3_rtree_query_callback(
11436
sqlite3 *db,
11437
const char *zQueryFunc,
11438
int (*xQueryFunc)(sqlite3_rtree_query_info*),
11439
void *pContext,
11440
void (*xDestructor)(void*)
11441
);
11442
11443
11444
/*
11445
** A pointer to a structure of the following type is passed as the
11446
** argument to scored geometry callback registered using
11447
** sqlite3_rtree_query_callback().
11448
**
11449
** Note that the first 5 fields of this structure are identical to
11450
** sqlite3_rtree_geometry. This structure is a subclass of
11451
** sqlite3_rtree_geometry.
11452
*/
11453
struct sqlite3_rtree_query_info {
11454
void *pContext; /* pContext from when function registered */
11455
int nParam; /* Number of function parameters */
11456
sqlite3_rtree_dbl *aParam; /* value of function parameters */
11457
void *pUser; /* callback can use this, if desired */
11458
void (*xDelUser)(void*); /* function to free pUser */
11459
sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */
11460
unsigned int *anQueue; /* Number of pending entries in the queue */
11461
int nCoord; /* Number of coordinates */
11462
int iLevel; /* Level of current node or entry */
11463
int mxLevel; /* The largest iLevel value in the tree */
11464
sqlite3_int64 iRowid; /* Rowid for current entry */
11465
sqlite3_rtree_dbl rParentScore; /* Score of parent node */
11466
int eParentWithin; /* Visibility of parent node */
11467
int eWithin; /* OUT: Visibility */
11468
sqlite3_rtree_dbl rScore; /* OUT: Write the score here */
11469
/* The following fields are only available in 3.8.11 and later */
11470
sqlite3_value **apSqlParam; /* Original SQL values of parameters */
11471
};
11472
11473
/*
11474
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
11475
*/
11476
#define NOT_WITHIN 0 /* Object completely outside of query region */
11477
#define PARTLY_WITHIN 1 /* Object partially overlaps query region */
11478
#define FULLY_WITHIN 2 /* Object fully contained within query region */
11479
11480
11481
#ifdef __cplusplus
11482
} /* end of the 'extern "C"' block */
11483
#endif
11484
11485
#endif /* ifndef _SQLITE3RTREE_H_ */
11486
11487
/******** End of sqlite3rtree.h *********/
11488
/******** Begin file sqlite3session.h *********/
11489
11490
#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
11491
#define __SQLITESESSION_H_ 1
11492
11493
/*
11494
** Make sure we can call this stuff from C++.
11495
*/
11496
#ifdef __cplusplus
11497
extern "C" {
11498
#endif
11499
11500
11501
/*
11502
** CAPI3REF: Session Object Handle
11503
**
11504
** An instance of this object is a [session] that can be used to
11505
** record changes to a database.
11506
*/
11507
typedef struct sqlite3_session sqlite3_session;
11508
11509
/*
11510
** CAPI3REF: Changeset Iterator Handle
11511
**
11512
** An instance of this object acts as a cursor for iterating
11513
** over the elements of a [changeset] or [patchset].
11514
*/
11515
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
11516
11517
/*
11518
** CAPI3REF: Create A New Session Object
11519
** CONSTRUCTOR: sqlite3_session
11520
**
11521
** Create a new session object attached to database handle db. If successful,
11522
** a pointer to the new object is written to *ppSession and SQLITE_OK is
11523
** returned. If an error occurs, *ppSession is set to NULL and an SQLite
11524
** error code (e.g. SQLITE_NOMEM) is returned.
11525
**
11526
** It is possible to create multiple session objects attached to a single
11527
** database handle.
11528
**
11529
** Session objects created using this function should be deleted using the
11530
** [sqlite3session_delete()] function before the database handle that they
11531
** are attached to is itself closed. If the database handle is closed before
11532
** the session object is deleted, then the results of calling any session
11533
** module function, including [sqlite3session_delete()] on the session object
11534
** are undefined.
11535
**
11536
** Because the session module uses the [sqlite3_preupdate_hook()] API, it
11537
** is not possible for an application to register a pre-update hook on a
11538
** database handle that has one or more session objects attached. Nor is
11539
** it possible to create a session object attached to a database handle for
11540
** which a pre-update hook is already defined. The results of attempting
11541
** either of these things are undefined.
11542
**
11543
** The session object will be used to create changesets for tables in
11544
** database zDb, where zDb is either "main", or "temp", or the name of an
11545
** attached database. It is not an error if database zDb is not attached
11546
** to the database when the session object is created.
11547
*/
11548
SQLITE_API int sqlite3session_create(
11549
sqlite3 *db, /* Database handle */
11550
const char *zDb, /* Name of db (e.g. "main") */
11551
sqlite3_session **ppSession /* OUT: New session object */
11552
);
11553
11554
/*
11555
** CAPI3REF: Delete A Session Object
11556
** DESTRUCTOR: sqlite3_session
11557
**
11558
** Delete a session object previously allocated using
11559
** [sqlite3session_create()]. Once a session object has been deleted, the
11560
** results of attempting to use pSession with any other session module
11561
** function are undefined.
11562
**
11563
** Session objects must be deleted before the database handle to which they
11564
** are attached is closed. Refer to the documentation for
11565
** [sqlite3session_create()] for details.
11566
*/
11567
SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
11568
11569
/*
11570
** CAPI3REF: Configure a Session Object
11571
** METHOD: sqlite3_session
11572
**
11573
** This method is used to configure a session object after it has been
11574
** created. At present the only valid values for the second parameter are
11575
** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID].
11576
**
11577
*/
11578
SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
11579
11580
/*
11581
** CAPI3REF: Options for sqlite3session_object_config
11582
**
11583
** The following values may passed as the the 2nd parameter to
11584
** sqlite3session_object_config().
11585
**
11586
** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
11587
** This option is used to set, clear or query the flag that enables
11588
** the [sqlite3session_changeset_size()] API. Because it imposes some
11589
** computational overhead, this API is disabled by default. Argument
11590
** pArg must point to a value of type (int). If the value is initially
11591
** 0, then the sqlite3session_changeset_size() API is disabled. If it
11592
** is greater than 0, then the same API is enabled. Or, if the initial
11593
** value is less than zero, no change is made. In all cases the (int)
11594
** variable is set to 1 if the sqlite3session_changeset_size() API is
11595
** enabled following the current call, or 0 otherwise.
11596
**
11597
** It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11598
** the first table has been attached to the session object.
11599
**
11600
** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd>
11601
** This option is used to set, clear or query the flag that enables
11602
** collection of data for tables with no explicit PRIMARY KEY.
11603
**
11604
** Normally, tables with no explicit PRIMARY KEY are simply ignored
11605
** by the sessions module. However, if this flag is set, it behaves
11606
** as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted
11607
** as their leftmost columns.
11608
**
11609
** It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11610
** the first table has been attached to the session object.
11611
*/
11612
#define SQLITE_SESSION_OBJCONFIG_SIZE 1
11613
#define SQLITE_SESSION_OBJCONFIG_ROWID 2
11614
11615
/*
11616
** CAPI3REF: Enable Or Disable A Session Object
11617
** METHOD: sqlite3_session
11618
**
11619
** Enable or disable the recording of changes by a session object. When
11620
** enabled, a session object records changes made to the database. When
11621
** disabled - it does not. A newly created session object is enabled.
11622
** Refer to the documentation for [sqlite3session_changeset()] for further
11623
** details regarding how enabling and disabling a session object affects
11624
** the eventual changesets.
11625
**
11626
** Passing zero to this function disables the session. Passing a value
11627
** greater than zero enables it. Passing a value less than zero is a
11628
** no-op, and may be used to query the current state of the session.
11629
**
11630
** The return value indicates the final state of the session object: 0 if
11631
** the session is disabled, or 1 if it is enabled.
11632
*/
11633
SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
11634
11635
/*
11636
** CAPI3REF: Set Or Clear the Indirect Change Flag
11637
** METHOD: sqlite3_session
11638
**
11639
** Each change recorded by a session object is marked as either direct or
11640
** indirect. A change is marked as indirect if either:
11641
**
11642
** <ul>
11643
** <li> The session object "indirect" flag is set when the change is
11644
** made, or
11645
** <li> The change is made by an SQL trigger or foreign key action
11646
** instead of directly as a result of a users SQL statement.
11647
** </ul>
11648
**
11649
** If a single row is affected by more than one operation within a session,
11650
** then the change is considered indirect if all operations meet the criteria
11651
** for an indirect change above, or direct otherwise.
11652
**
11653
** This function is used to set, clear or query the session object indirect
11654
** flag. If the second argument passed to this function is zero, then the
11655
** indirect flag is cleared. If it is greater than zero, the indirect flag
11656
** is set. Passing a value less than zero does not modify the current value
11657
** of the indirect flag, and may be used to query the current state of the
11658
** indirect flag for the specified session object.
11659
**
11660
** The return value indicates the final state of the indirect flag: 0 if
11661
** it is clear, or 1 if it is set.
11662
*/
11663
SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
11664
11665
/*
11666
** CAPI3REF: Attach A Table To A Session Object
11667
** METHOD: sqlite3_session
11668
**
11669
** If argument zTab is not NULL, then it is the name of a table to attach
11670
** to the session object passed as the first argument. All subsequent changes
11671
** made to the table while the session object is enabled will be recorded. See
11672
** documentation for [sqlite3session_changeset()] for further details.
11673
**
11674
** Or, if argument zTab is NULL, then changes are recorded for all tables
11675
** in the database. If additional tables are added to the database (by
11676
** executing "CREATE TABLE" statements) after this call is made, changes for
11677
** the new tables are also recorded.
11678
**
11679
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
11680
** defined as part of their CREATE TABLE statement. It does not matter if the
11681
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
11682
** KEY may consist of a single column, or may be a composite key.
11683
**
11684
** It is not an error if the named table does not exist in the database. Nor
11685
** is it an error if the named table does not have a PRIMARY KEY. However,
11686
** no changes will be recorded in either of these scenarios.
11687
**
11688
** Changes are not recorded for individual rows that have NULL values stored
11689
** in one or more of their PRIMARY KEY columns.
11690
**
11691
** SQLITE_OK is returned if the call completes without error. Or, if an error
11692
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
11693
**
11694
** <h3>Special sqlite_stat1 Handling</h3>
11695
**
11696
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
11697
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
11698
** <pre>
11699
** &nbsp; CREATE TABLE sqlite_stat1(tbl,idx,stat)
11700
** </pre>
11701
**
11702
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
11703
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
11704
** are recorded for rows for which (idx IS NULL) is true. However, for such
11705
** rows a zero-length blob (SQL value X'') is stored in the changeset or
11706
** patchset instead of a NULL value. This allows such changesets to be
11707
** manipulated by legacy implementations of sqlite3changeset_invert(),
11708
** concat() and similar.
11709
**
11710
** The sqlite3changeset_apply() function automatically converts the
11711
** zero-length blob back to a NULL value when updating the sqlite_stat1
11712
** table. However, if the application calls sqlite3changeset_new(),
11713
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
11714
** iterator directly (including on a changeset iterator passed to a
11715
** conflict-handler callback) then the X'' value is returned. The application
11716
** must translate X'' to NULL itself if required.
11717
**
11718
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
11719
** changes made to the sqlite_stat1 table. Legacy versions of the
11720
** sqlite3changeset_apply() function silently ignore any modifications to the
11721
** sqlite_stat1 table that are part of a changeset or patchset.
11722
*/
11723
SQLITE_API int sqlite3session_attach(
11724
sqlite3_session *pSession, /* Session object */
11725
const char *zTab /* Table name */
11726
);
11727
11728
/*
11729
** CAPI3REF: Set a table filter on a Session Object.
11730
** METHOD: sqlite3_session
11731
**
11732
** The second argument (xFilter) is the "filter callback". For changes to rows
11733
** in tables that are not attached to the Session object, the filter is called
11734
** to determine whether changes to the table's rows should be tracked or not.
11735
** If xFilter returns 0, changes are not tracked. Note that once a table is
11736
** attached, xFilter will not be called again.
11737
*/
11738
SQLITE_API void sqlite3session_table_filter(
11739
sqlite3_session *pSession, /* Session object */
11740
int(*xFilter)(
11741
void *pCtx, /* Copy of third arg to _filter_table() */
11742
const char *zTab /* Table name */
11743
),
11744
void *pCtx /* First argument passed to xFilter */
11745
);
11746
11747
/*
11748
** CAPI3REF: Generate A Changeset From A Session Object
11749
** METHOD: sqlite3_session
11750
**
11751
** Obtain a changeset containing changes to the tables attached to the
11752
** session object passed as the first argument. If successful,
11753
** set *ppChangeset to point to a buffer containing the changeset
11754
** and *pnChangeset to the size of the changeset in bytes before returning
11755
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
11756
** zero and return an SQLite error code.
11757
**
11758
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
11759
** each representing a change to a single row of an attached table. An INSERT
11760
** change contains the values of each field of a new database row. A DELETE
11761
** contains the original values of each field of a deleted database row. An
11762
** UPDATE change contains the original values of each field of an updated
11763
** database row along with the updated values for each updated non-primary-key
11764
** column. It is not possible for an UPDATE change to represent a change that
11765
** modifies the values of primary key columns. If such a change is made, it
11766
** is represented in a changeset as a DELETE followed by an INSERT.
11767
**
11768
** Changes are not recorded for rows that have NULL values stored in one or
11769
** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
11770
** no corresponding change is present in the changesets returned by this
11771
** function. If an existing row with one or more NULL values stored in
11772
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
11773
** only an INSERT is appears in the changeset. Similarly, if an existing row
11774
** with non-NULL PRIMARY KEY values is updated so that one or more of its
11775
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
11776
** DELETE change only.
11777
**
11778
** The contents of a changeset may be traversed using an iterator created
11779
** using the [sqlite3changeset_start()] API. A changeset may be applied to
11780
** a database with a compatible schema using the [sqlite3changeset_apply()]
11781
** API.
11782
**
11783
** Within a changeset generated by this function, all changes related to a
11784
** single table are grouped together. In other words, when iterating through
11785
** a changeset or when applying a changeset to a database, all changes related
11786
** to a single table are processed before moving on to the next table. Tables
11787
** are sorted in the same order in which they were attached (or auto-attached)
11788
** to the sqlite3_session object. The order in which the changes related to
11789
** a single table are stored is undefined.
11790
**
11791
** Following a successful call to this function, it is the responsibility of
11792
** the caller to eventually free the buffer that *ppChangeset points to using
11793
** [sqlite3_free()].
11794
**
11795
** <h3>Changeset Generation</h3>
11796
**
11797
** Once a table has been attached to a session object, the session object
11798
** records the primary key values of all new rows inserted into the table.
11799
** It also records the original primary key and other column values of any
11800
** deleted or updated rows. For each unique primary key value, data is only
11801
** recorded once - the first time a row with said primary key is inserted,
11802
** updated or deleted in the lifetime of the session.
11803
**
11804
** There is one exception to the previous paragraph: when a row is inserted,
11805
** updated or deleted, if one or more of its primary key columns contain a
11806
** NULL value, no record of the change is made.
11807
**
11808
** The session object therefore accumulates two types of records - those
11809
** that consist of primary key values only (created when the user inserts
11810
** a new record) and those that consist of the primary key values and the
11811
** original values of other table columns (created when the users deletes
11812
** or updates a record).
11813
**
11814
** When this function is called, the requested changeset is created using
11815
** both the accumulated records and the current contents of the database
11816
** file. Specifically:
11817
**
11818
** <ul>
11819
** <li> For each record generated by an insert, the database is queried
11820
** for a row with a matching primary key. If one is found, an INSERT
11821
** change is added to the changeset. If no such row is found, no change
11822
** is added to the changeset.
11823
**
11824
** <li> For each record generated by an update or delete, the database is
11825
** queried for a row with a matching primary key. If such a row is
11826
** found and one or more of the non-primary key fields have been
11827
** modified from their original values, an UPDATE change is added to
11828
** the changeset. Or, if no such row is found in the table, a DELETE
11829
** change is added to the changeset. If there is a row with a matching
11830
** primary key in the database, but all fields contain their original
11831
** values, no change is added to the changeset.
11832
** </ul>
11833
**
11834
** This means, amongst other things, that if a row is inserted and then later
11835
** deleted while a session object is active, neither the insert nor the delete
11836
** will be present in the changeset. Or if a row is deleted and then later a
11837
** row with the same primary key values inserted while a session object is
11838
** active, the resulting changeset will contain an UPDATE change instead of
11839
** a DELETE and an INSERT.
11840
**
11841
** When a session object is disabled (see the [sqlite3session_enable()] API),
11842
** it does not accumulate records when rows are inserted, updated or deleted.
11843
** This may appear to have some counter-intuitive effects if a single row
11844
** is written to more than once during a session. For example, if a row
11845
** is inserted while a session object is enabled, then later deleted while
11846
** the same session object is disabled, no INSERT record will appear in the
11847
** changeset, even though the delete took place while the session was disabled.
11848
** Or, if one field of a row is updated while a session is enabled, and
11849
** then another field of the same row is updated while the session is disabled,
11850
** the resulting changeset will contain an UPDATE change that updates both
11851
** fields.
11852
*/
11853
SQLITE_API int sqlite3session_changeset(
11854
sqlite3_session *pSession, /* Session object */
11855
int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */
11856
void **ppChangeset /* OUT: Buffer containing changeset */
11857
);
11858
11859
/*
11860
** CAPI3REF: Return An Upper-limit For The Size Of The Changeset
11861
** METHOD: sqlite3_session
11862
**
11863
** By default, this function always returns 0. For it to return
11864
** a useful result, the sqlite3_session object must have been configured
11865
** to enable this API using sqlite3session_object_config() with the
11866
** SQLITE_SESSION_OBJCONFIG_SIZE verb.
11867
**
11868
** When enabled, this function returns an upper limit, in bytes, for the size
11869
** of the changeset that might be produced if sqlite3session_changeset() were
11870
** called. The final changeset size might be equal to or smaller than the
11871
** size in bytes returned by this function.
11872
*/
11873
SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession);
11874
11875
/*
11876
** CAPI3REF: Load The Difference Between Tables Into A Session
11877
** METHOD: sqlite3_session
11878
**
11879
** If it is not already attached to the session object passed as the first
11880
** argument, this function attaches table zTbl in the same manner as the
11881
** [sqlite3session_attach()] function. If zTbl does not exist, or if it
11882
** does not have a primary key, this function is a no-op (but does not return
11883
** an error).
11884
**
11885
** Argument zFromDb must be the name of a database ("main", "temp" etc.)
11886
** attached to the same database handle as the session object that contains
11887
** a table compatible with the table attached to the session by this function.
11888
** A table is considered compatible if it:
11889
**
11890
** <ul>
11891
** <li> Has the same name,
11892
** <li> Has the same set of columns declared in the same order, and
11893
** <li> Has the same PRIMARY KEY definition.
11894
** </ul>
11895
**
11896
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
11897
** are compatible but do not have any PRIMARY KEY columns, it is not an error
11898
** but no changes are added to the session object. As with other session
11899
** APIs, tables without PRIMARY KEYs are simply ignored.
11900
**
11901
** This function adds a set of changes to the session object that could be
11902
** used to update the table in database zFrom (call this the "from-table")
11903
** so that its content is the same as the table attached to the session
11904
** object (call this the "to-table"). Specifically:
11905
**
11906
** <ul>
11907
** <li> For each row (primary key) that exists in the to-table but not in
11908
** the from-table, an INSERT record is added to the session object.
11909
**
11910
** <li> For each row (primary key) that exists in the to-table but not in
11911
** the from-table, a DELETE record is added to the session object.
11912
**
11913
** <li> For each row (primary key) that exists in both tables, but features
11914
** different non-PK values in each, an UPDATE record is added to the
11915
** session.
11916
** </ul>
11917
**
11918
** To clarify, if this function is called and then a changeset constructed
11919
** using [sqlite3session_changeset()], then after applying that changeset to
11920
** database zFrom the contents of the two compatible tables would be
11921
** identical.
11922
**
11923
** Unless the call to this function is a no-op as described above, it is an
11924
** error if database zFrom does not exist or does not contain the required
11925
** compatible table.
11926
**
11927
** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
11928
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
11929
** may be set to point to a buffer containing an English language error
11930
** message. It is the responsibility of the caller to free this buffer using
11931
** sqlite3_free().
11932
*/
11933
SQLITE_API int sqlite3session_diff(
11934
sqlite3_session *pSession,
11935
const char *zFromDb,
11936
const char *zTbl,
11937
char **pzErrMsg
11938
);
11939
11940
11941
/*
11942
** CAPI3REF: Generate A Patchset From A Session Object
11943
** METHOD: sqlite3_session
11944
**
11945
** The differences between a patchset and a changeset are that:
11946
**
11947
** <ul>
11948
** <li> DELETE records consist of the primary key fields only. The
11949
** original values of other fields are omitted.
11950
** <li> The original values of any modified fields are omitted from
11951
** UPDATE records.
11952
** </ul>
11953
**
11954
** A patchset blob may be used with up to date versions of all
11955
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
11956
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
11957
** attempting to use a patchset blob with old versions of the
11958
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
11959
**
11960
** Because the non-primary key "old.*" fields are omitted, no
11961
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
11962
** is passed to the sqlite3changeset_apply() API. Other conflict types work
11963
** in the same way as for changesets.
11964
**
11965
** Changes within a patchset are ordered in the same way as for changesets
11966
** generated by the sqlite3session_changeset() function (i.e. all changes for
11967
** a single table are grouped together, tables appear in the order in which
11968
** they were attached to the session object).
11969
*/
11970
SQLITE_API int sqlite3session_patchset(
11971
sqlite3_session *pSession, /* Session object */
11972
int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */
11973
void **ppPatchset /* OUT: Buffer containing patchset */
11974
);
11975
11976
/*
11977
** CAPI3REF: Test if a changeset has recorded any changes.
11978
**
11979
** Return non-zero if no changes to attached tables have been recorded by
11980
** the session object passed as the first argument. Otherwise, if one or
11981
** more changes have been recorded, return zero.
11982
**
11983
** Even if this function returns zero, it is possible that calling
11984
** [sqlite3session_changeset()] on the session handle may still return a
11985
** changeset that contains no changes. This can happen when a row in
11986
** an attached table is modified and then later on the original values
11987
** are restored. However, if this function returns non-zero, then it is
11988
** guaranteed that a call to sqlite3session_changeset() will return a
11989
** changeset containing zero changes.
11990
*/
11991
SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
11992
11993
/*
11994
** CAPI3REF: Query for the amount of heap memory used by a session object.
11995
**
11996
** This API returns the total amount of heap memory in bytes currently
11997
** used by the session object passed as the only argument.
11998
*/
11999
SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession);
12000
12001
/*
12002
** CAPI3REF: Create An Iterator To Traverse A Changeset
12003
** CONSTRUCTOR: sqlite3_changeset_iter
12004
**
12005
** Create an iterator used to iterate through the contents of a changeset.
12006
** If successful, *pp is set to point to the iterator handle and SQLITE_OK
12007
** is returned. Otherwise, if an error occurs, *pp is set to zero and an
12008
** SQLite error code is returned.
12009
**
12010
** The following functions can be used to advance and query a changeset
12011
** iterator created by this function:
12012
**
12013
** <ul>
12014
** <li> [sqlite3changeset_next()]
12015
** <li> [sqlite3changeset_op()]
12016
** <li> [sqlite3changeset_new()]
12017
** <li> [sqlite3changeset_old()]
12018
** </ul>
12019
**
12020
** It is the responsibility of the caller to eventually destroy the iterator
12021
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
12022
** changeset (pChangeset) must remain valid until after the iterator is
12023
** destroyed.
12024
**
12025
** Assuming the changeset blob was created by one of the
12026
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
12027
** [sqlite3changeset_invert()] functions, all changes within the changeset
12028
** that apply to a single table are grouped together. This means that when
12029
** an application iterates through a changeset using an iterator created by
12030
** this function, all changes that relate to a single table are visited
12031
** consecutively. There is no chance that the iterator will visit a change
12032
** the applies to table X, then one for table Y, and then later on visit
12033
** another change for table X.
12034
**
12035
** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
12036
** may be modified by passing a combination of
12037
** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
12038
**
12039
** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
12040
** and therefore subject to change.
12041
*/
12042
SQLITE_API int sqlite3changeset_start(
12043
sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
12044
int nChangeset, /* Size of changeset blob in bytes */
12045
void *pChangeset /* Pointer to blob containing changeset */
12046
);
12047
SQLITE_API int sqlite3changeset_start_v2(
12048
sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */
12049
int nChangeset, /* Size of changeset blob in bytes */
12050
void *pChangeset, /* Pointer to blob containing changeset */
12051
int flags /* SESSION_CHANGESETSTART_* flags */
12052
);
12053
12054
/*
12055
** CAPI3REF: Flags for sqlite3changeset_start_v2
12056
**
12057
** The following flags may passed via the 4th parameter to
12058
** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
12059
**
12060
** <dt>SQLITE_CHANGESETSTART_INVERT <dd>
12061
** Invert the changeset while iterating through it. This is equivalent to
12062
** inverting a changeset using sqlite3changeset_invert() before applying it.
12063
** It is an error to specify this flag with a patchset.
12064
*/
12065
#define SQLITE_CHANGESETSTART_INVERT 0x0002
12066
12067
12068
/*
12069
** CAPI3REF: Advance A Changeset Iterator
12070
** METHOD: sqlite3_changeset_iter
12071
**
12072
** This function may only be used with iterators created by the function
12073
** [sqlite3changeset_start()]. If it is called on an iterator passed to
12074
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
12075
** is returned and the call has no effect.
12076
**
12077
** Immediately after an iterator is created by sqlite3changeset_start(), it
12078
** does not point to any change in the changeset. Assuming the changeset
12079
** is not empty, the first call to this function advances the iterator to
12080
** point to the first change in the changeset. Each subsequent call advances
12081
** the iterator to point to the next change in the changeset (if any). If
12082
** no error occurs and the iterator points to a valid change after a call
12083
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
12084
** Otherwise, if all changes in the changeset have already been visited,
12085
** SQLITE_DONE is returned.
12086
**
12087
** If an error occurs, an SQLite error code is returned. Possible error
12088
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
12089
** SQLITE_NOMEM.
12090
*/
12091
SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
12092
12093
/*
12094
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
12095
** METHOD: sqlite3_changeset_iter
12096
**
12097
** The pIter argument passed to this function may either be an iterator
12098
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
12099
** created by [sqlite3changeset_start()]. In the latter case, the most recent
12100
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
12101
** is not the case, this function returns [SQLITE_MISUSE].
12102
**
12103
** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three
12104
** outputs are set through these pointers:
12105
**
12106
** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
12107
** depending on the type of change that the iterator currently points to;
12108
**
12109
** *pnCol is set to the number of columns in the table affected by the change; and
12110
**
12111
** *pzTab is set to point to a nul-terminated utf-8 encoded string containing
12112
** the name of the table affected by the current change. The buffer remains
12113
** valid until either sqlite3changeset_next() is called on the iterator
12114
** or until the conflict-handler function returns.
12115
**
12116
** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
12117
** is an indirect change, or false (0) otherwise. See the documentation for
12118
** [sqlite3session_indirect()] for a description of direct and indirect
12119
** changes.
12120
**
12121
** If no error occurs, SQLITE_OK is returned. If an error does occur, an
12122
** SQLite error code is returned. The values of the output variables may not
12123
** be trusted in this case.
12124
*/
12125
SQLITE_API int sqlite3changeset_op(
12126
sqlite3_changeset_iter *pIter, /* Iterator object */
12127
const char **pzTab, /* OUT: Pointer to table name */
12128
int *pnCol, /* OUT: Number of columns in table */
12129
int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */
12130
int *pbIndirect /* OUT: True for an 'indirect' change */
12131
);
12132
12133
/*
12134
** CAPI3REF: Obtain The Primary Key Definition Of A Table
12135
** METHOD: sqlite3_changeset_iter
12136
**
12137
** For each modified table, a changeset includes the following:
12138
**
12139
** <ul>
12140
** <li> The number of columns in the table, and
12141
** <li> Which of those columns make up the tables PRIMARY KEY.
12142
** </ul>
12143
**
12144
** This function is used to find which columns comprise the PRIMARY KEY of
12145
** the table modified by the change that iterator pIter currently points to.
12146
** If successful, *pabPK is set to point to an array of nCol entries, where
12147
** nCol is the number of columns in the table. Elements of *pabPK are set to
12148
** 0x01 if the corresponding column is part of the tables primary key, or
12149
** 0x00 if it is not.
12150
**
12151
** If argument pnCol is not NULL, then *pnCol is set to the number of columns
12152
** in the table.
12153
**
12154
** If this function is called when the iterator does not point to a valid
12155
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
12156
** SQLITE_OK is returned and the output variables populated as described
12157
** above.
12158
*/
12159
SQLITE_API int sqlite3changeset_pk(
12160
sqlite3_changeset_iter *pIter, /* Iterator object */
12161
unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */
12162
int *pnCol /* OUT: Number of entries in output array */
12163
);
12164
12165
/*
12166
** CAPI3REF: Obtain old.* Values From A Changeset Iterator
12167
** METHOD: sqlite3_changeset_iter
12168
**
12169
** The pIter argument passed to this function may either be an iterator
12170
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
12171
** created by [sqlite3changeset_start()]. In the latter case, the most recent
12172
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
12173
** Furthermore, it may only be called if the type of change that the iterator
12174
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
12175
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
12176
**
12177
** Argument iVal must be greater than or equal to 0, and less than the number
12178
** of columns in the table affected by the current change. Otherwise,
12179
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
12180
**
12181
** If successful, this function sets *ppValue to point to a protected
12182
** sqlite3_value object containing the iVal'th value from the vector of
12183
** original row values stored as part of the UPDATE or DELETE change and
12184
** returns SQLITE_OK. The name of the function comes from the fact that this
12185
** is similar to the "old.*" columns available to update or delete triggers.
12186
**
12187
** If some other error occurs (e.g. an OOM condition), an SQLite error code
12188
** is returned and *ppValue is set to NULL.
12189
*/
12190
SQLITE_API int sqlite3changeset_old(
12191
sqlite3_changeset_iter *pIter, /* Changeset iterator */
12192
int iVal, /* Column number */
12193
sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */
12194
);
12195
12196
/*
12197
** CAPI3REF: Obtain new.* Values From A Changeset Iterator
12198
** METHOD: sqlite3_changeset_iter
12199
**
12200
** The pIter argument passed to this function may either be an iterator
12201
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
12202
** created by [sqlite3changeset_start()]. In the latter case, the most recent
12203
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
12204
** Furthermore, it may only be called if the type of change that the iterator
12205
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
12206
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
12207
**
12208
** Argument iVal must be greater than or equal to 0, and less than the number
12209
** of columns in the table affected by the current change. Otherwise,
12210
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
12211
**
12212
** If successful, this function sets *ppValue to point to a protected
12213
** sqlite3_value object containing the iVal'th value from the vector of
12214
** new row values stored as part of the UPDATE or INSERT change and
12215
** returns SQLITE_OK. If the change is an UPDATE and does not include
12216
** a new value for the requested column, *ppValue is set to NULL and
12217
** SQLITE_OK returned. The name of the function comes from the fact that
12218
** this is similar to the "new.*" columns available to update or delete
12219
** triggers.
12220
**
12221
** If some other error occurs (e.g. an OOM condition), an SQLite error code
12222
** is returned and *ppValue is set to NULL.
12223
*/
12224
SQLITE_API int sqlite3changeset_new(
12225
sqlite3_changeset_iter *pIter, /* Changeset iterator */
12226
int iVal, /* Column number */
12227
sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */
12228
);
12229
12230
/*
12231
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
12232
** METHOD: sqlite3_changeset_iter
12233
**
12234
** This function should only be used with iterator objects passed to a
12235
** conflict-handler callback by [sqlite3changeset_apply()] with either
12236
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
12237
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
12238
** is set to NULL.
12239
**
12240
** Argument iVal must be greater than or equal to 0, and less than the number
12241
** of columns in the table affected by the current change. Otherwise,
12242
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
12243
**
12244
** If successful, this function sets *ppValue to point to a protected
12245
** sqlite3_value object containing the iVal'th value from the
12246
** "conflicting row" associated with the current conflict-handler callback
12247
** and returns SQLITE_OK.
12248
**
12249
** If some other error occurs (e.g. an OOM condition), an SQLite error code
12250
** is returned and *ppValue is set to NULL.
12251
*/
12252
SQLITE_API int sqlite3changeset_conflict(
12253
sqlite3_changeset_iter *pIter, /* Changeset iterator */
12254
int iVal, /* Column number */
12255
sqlite3_value **ppValue /* OUT: Value from conflicting row */
12256
);
12257
12258
/*
12259
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
12260
** METHOD: sqlite3_changeset_iter
12261
**
12262
** This function may only be called with an iterator passed to an
12263
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
12264
** it sets the output variable to the total number of known foreign key
12265
** violations in the destination database and returns SQLITE_OK.
12266
**
12267
** In all other cases this function returns SQLITE_MISUSE.
12268
*/
12269
SQLITE_API int sqlite3changeset_fk_conflicts(
12270
sqlite3_changeset_iter *pIter, /* Changeset iterator */
12271
int *pnOut /* OUT: Number of FK violations */
12272
);
12273
12274
12275
/*
12276
** CAPI3REF: Finalize A Changeset Iterator
12277
** METHOD: sqlite3_changeset_iter
12278
**
12279
** This function is used to finalize an iterator allocated with
12280
** [sqlite3changeset_start()].
12281
**
12282
** This function should only be called on iterators created using the
12283
** [sqlite3changeset_start()] function. If an application calls this
12284
** function with an iterator passed to a conflict-handler by
12285
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
12286
** call has no effect.
12287
**
12288
** If an error was encountered within a call to an sqlite3changeset_xxx()
12289
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
12290
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
12291
** to that error is returned by this function. Otherwise, SQLITE_OK is
12292
** returned. This is to allow the following pattern (pseudo-code):
12293
**
12294
** <pre>
12295
** sqlite3changeset_start();
12296
** while( SQLITE_ROW==sqlite3changeset_next() ){
12297
** // Do something with change.
12298
** }
12299
** rc = sqlite3changeset_finalize();
12300
** if( rc!=SQLITE_OK ){
12301
** // An error has occurred
12302
** }
12303
** </pre>
12304
*/
12305
SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
12306
12307
/*
12308
** CAPI3REF: Invert A Changeset
12309
**
12310
** This function is used to "invert" a changeset object. Applying an inverted
12311
** changeset to a database reverses the effects of applying the uninverted
12312
** changeset. Specifically:
12313
**
12314
** <ul>
12315
** <li> Each DELETE change is changed to an INSERT, and
12316
** <li> Each INSERT change is changed to a DELETE, and
12317
** <li> For each UPDATE change, the old.* and new.* values are exchanged.
12318
** </ul>
12319
**
12320
** This function does not change the order in which changes appear within
12321
** the changeset. It merely reverses the sense of each individual change.
12322
**
12323
** If successful, a pointer to a buffer containing the inverted changeset
12324
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
12325
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
12326
** zeroed and an SQLite error code returned.
12327
**
12328
** It is the responsibility of the caller to eventually call sqlite3_free()
12329
** on the *ppOut pointer to free the buffer allocation following a successful
12330
** call to this function.
12331
**
12332
** WARNING/TODO: This function currently assumes that the input is a valid
12333
** changeset. If it is not, the results are undefined.
12334
*/
12335
SQLITE_API int sqlite3changeset_invert(
12336
int nIn, const void *pIn, /* Input changeset */
12337
int *pnOut, void **ppOut /* OUT: Inverse of input */
12338
);
12339
12340
/*
12341
** CAPI3REF: Concatenate Two Changeset Objects
12342
**
12343
** This function is used to concatenate two changesets, A and B, into a
12344
** single changeset. The result is a changeset equivalent to applying
12345
** changeset A followed by changeset B.
12346
**
12347
** This function combines the two input changesets using an
12348
** sqlite3_changegroup object. Calling it produces similar results as the
12349
** following code fragment:
12350
**
12351
** <pre>
12352
** sqlite3_changegroup *pGrp;
12353
** rc = sqlite3_changegroup_new(&pGrp);
12354
** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
12355
** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
12356
** if( rc==SQLITE_OK ){
12357
** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
12358
** }else{
12359
** *ppOut = 0;
12360
** *pnOut = 0;
12361
** }
12362
** </pre>
12363
**
12364
** Refer to the sqlite3_changegroup documentation below for details.
12365
*/
12366
SQLITE_API int sqlite3changeset_concat(
12367
int nA, /* Number of bytes in buffer pA */
12368
void *pA, /* Pointer to buffer containing changeset A */
12369
int nB, /* Number of bytes in buffer pB */
12370
void *pB, /* Pointer to buffer containing changeset B */
12371
int *pnOut, /* OUT: Number of bytes in output changeset */
12372
void **ppOut /* OUT: Buffer containing output changeset */
12373
);
12374
12375
/*
12376
** CAPI3REF: Changegroup Handle
12377
**
12378
** A changegroup is an object used to combine two or more
12379
** [changesets] or [patchsets]
12380
*/
12381
typedef struct sqlite3_changegroup sqlite3_changegroup;
12382
12383
/*
12384
** CAPI3REF: Create A New Changegroup Object
12385
** CONSTRUCTOR: sqlite3_changegroup
12386
**
12387
** An sqlite3_changegroup object is used to combine two or more changesets
12388
** (or patchsets) into a single changeset (or patchset). A single changegroup
12389
** object may combine changesets or patchsets, but not both. The output is
12390
** always in the same format as the input.
12391
**
12392
** If successful, this function returns SQLITE_OK and populates (*pp) with
12393
** a pointer to a new sqlite3_changegroup object before returning. The caller
12394
** should eventually free the returned object using a call to
12395
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
12396
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
12397
**
12398
** The usual usage pattern for an sqlite3_changegroup object is as follows:
12399
**
12400
** <ul>
12401
** <li> It is created using a call to sqlite3changegroup_new().
12402
**
12403
** <li> Zero or more changesets (or patchsets) are added to the object
12404
** by calling sqlite3changegroup_add().
12405
**
12406
** <li> The result of combining all input changesets together is obtained
12407
** by the application via a call to sqlite3changegroup_output().
12408
**
12409
** <li> The object is deleted using a call to sqlite3changegroup_delete().
12410
** </ul>
12411
**
12412
** Any number of calls to add() and output() may be made between the calls to
12413
** new() and delete(), and in any order.
12414
**
12415
** As well as the regular sqlite3changegroup_add() and
12416
** sqlite3changegroup_output() functions, also available are the streaming
12417
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
12418
*/
12419
SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
12420
12421
/*
12422
** CAPI3REF: Add a Schema to a Changegroup
12423
** METHOD: sqlite3_changegroup_schema
12424
**
12425
** This method may be used to optionally enforce the rule that the changesets
12426
** added to the changegroup handle must match the schema of database zDb
12427
** ("main", "temp", or the name of an attached database). If
12428
** sqlite3changegroup_add() is called to add a changeset that is not compatible
12429
** with the configured schema, SQLITE_SCHEMA is returned and the changegroup
12430
** object is left in an undefined state.
12431
**
12432
** A changeset schema is considered compatible with the database schema in
12433
** the same way as for sqlite3changeset_apply(). Specifically, for each
12434
** table in the changeset, there exists a database table with:
12435
**
12436
** <ul>
12437
** <li> The name identified by the changeset, and
12438
** <li> at least as many columns as recorded in the changeset, and
12439
** <li> the primary key columns in the same position as recorded in
12440
** the changeset.
12441
** </ul>
12442
**
12443
** The output of the changegroup object always has the same schema as the
12444
** database nominated using this function. In cases where changesets passed
12445
** to sqlite3changegroup_add() have fewer columns than the corresponding table
12446
** in the database schema, these are filled in using the default column
12447
** values from the database schema. This makes it possible to combined
12448
** changesets that have different numbers of columns for a single table
12449
** within a changegroup, provided that they are otherwise compatible.
12450
*/
12451
SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb);
12452
12453
/*
12454
** CAPI3REF: Add A Changeset To A Changegroup
12455
** METHOD: sqlite3_changegroup
12456
**
12457
** Add all changes within the changeset (or patchset) in buffer pData (size
12458
** nData bytes) to the changegroup.
12459
**
12460
** If the buffer contains a patchset, then all prior calls to this function
12461
** on the same changegroup object must also have specified patchsets. Or, if
12462
** the buffer contains a changeset, so must have the earlier calls to this
12463
** function. Otherwise, SQLITE_ERROR is returned and no changes are added
12464
** to the changegroup.
12465
**
12466
** Rows within the changeset and changegroup are identified by the values in
12467
** their PRIMARY KEY columns. A change in the changeset is considered to
12468
** apply to the same row as a change already present in the changegroup if
12469
** the two rows have the same primary key.
12470
**
12471
** Changes to rows that do not already appear in the changegroup are
12472
** simply copied into it. Or, if both the new changeset and the changegroup
12473
** contain changes that apply to a single row, the final contents of the
12474
** changegroup depends on the type of each change, as follows:
12475
**
12476
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12477
** <tr><th style="white-space:pre">Existing Change </th>
12478
** <th style="white-space:pre">New Change </th>
12479
** <th>Output Change
12480
** <tr><td>INSERT <td>INSERT <td>
12481
** The new change is ignored. This case does not occur if the new
12482
** changeset was recorded immediately after the changesets already
12483
** added to the changegroup.
12484
** <tr><td>INSERT <td>UPDATE <td>
12485
** The INSERT change remains in the changegroup. The values in the
12486
** INSERT change are modified as if the row was inserted by the
12487
** existing change and then updated according to the new change.
12488
** <tr><td>INSERT <td>DELETE <td>
12489
** The existing INSERT is removed from the changegroup. The DELETE is
12490
** not added.
12491
** <tr><td>UPDATE <td>INSERT <td>
12492
** The new change is ignored. This case does not occur if the new
12493
** changeset was recorded immediately after the changesets already
12494
** added to the changegroup.
12495
** <tr><td>UPDATE <td>UPDATE <td>
12496
** The existing UPDATE remains within the changegroup. It is amended
12497
** so that the accompanying values are as if the row was updated once
12498
** by the existing change and then again by the new change.
12499
** <tr><td>UPDATE <td>DELETE <td>
12500
** The existing UPDATE is replaced by the new DELETE within the
12501
** changegroup.
12502
** <tr><td>DELETE <td>INSERT <td>
12503
** If one or more of the column values in the row inserted by the
12504
** new change differ from those in the row deleted by the existing
12505
** change, the existing DELETE is replaced by an UPDATE within the
12506
** changegroup. Otherwise, if the inserted row is exactly the same
12507
** as the deleted row, the existing DELETE is simply discarded.
12508
** <tr><td>DELETE <td>UPDATE <td>
12509
** The new change is ignored. This case does not occur if the new
12510
** changeset was recorded immediately after the changesets already
12511
** added to the changegroup.
12512
** <tr><td>DELETE <td>DELETE <td>
12513
** The new change is ignored. This case does not occur if the new
12514
** changeset was recorded immediately after the changesets already
12515
** added to the changegroup.
12516
** </table>
12517
**
12518
** If the new changeset contains changes to a table that is already present
12519
** in the changegroup, then the number of columns and the position of the
12520
** primary key columns for the table must be consistent. If this is not the
12521
** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup
12522
** object has been configured with a database schema using the
12523
** sqlite3changegroup_schema() API, then it is possible to combine changesets
12524
** with different numbers of columns for a single table, provided that
12525
** they are otherwise compatible.
12526
**
12527
** If the input changeset appears to be corrupt and the corruption is
12528
** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition
12529
** occurs during processing, this function returns SQLITE_NOMEM.
12530
**
12531
** In all cases, if an error occurs the state of the final contents of the
12532
** changegroup is undefined. If no error occurs, SQLITE_OK is returned.
12533
*/
12534
SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
12535
12536
/*
12537
** CAPI3REF: Add A Single Change To A Changegroup
12538
** METHOD: sqlite3_changegroup
12539
**
12540
** This function adds the single change currently indicated by the iterator
12541
** passed as the second argument to the changegroup object. The rules for
12542
** adding the change are just as described for [sqlite3changegroup_add()].
12543
**
12544
** If the change is successfully added to the changegroup, SQLITE_OK is
12545
** returned. Otherwise, an SQLite error code is returned.
12546
**
12547
** The iterator must point to a valid entry when this function is called.
12548
** If it does not, SQLITE_ERROR is returned and no change is added to the
12549
** changegroup. Additionally, the iterator must not have been opened with
12550
** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also
12551
** returned.
12552
*/
12553
SQLITE_API int sqlite3changegroup_add_change(
12554
sqlite3_changegroup*,
12555
sqlite3_changeset_iter*
12556
);
12557
12558
12559
12560
/*
12561
** CAPI3REF: Obtain A Composite Changeset From A Changegroup
12562
** METHOD: sqlite3_changegroup
12563
**
12564
** Obtain a buffer containing a changeset (or patchset) representing the
12565
** current contents of the changegroup. If the inputs to the changegroup
12566
** were themselves changesets, the output is a changeset. Or, if the
12567
** inputs were patchsets, the output is also a patchset.
12568
**
12569
** As with the output of the sqlite3session_changeset() and
12570
** sqlite3session_patchset() functions, all changes related to a single
12571
** table are grouped together in the output of this function. Tables appear
12572
** in the same order as for the very first changeset added to the changegroup.
12573
** If the second or subsequent changesets added to the changegroup contain
12574
** changes for tables that do not appear in the first changeset, they are
12575
** appended onto the end of the output changeset, again in the order in
12576
** which they are first encountered.
12577
**
12578
** If an error occurs, an SQLite error code is returned and the output
12579
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
12580
** is returned and the output variables are set to the size of and a
12581
** pointer to the output buffer, respectively. In this case it is the
12582
** responsibility of the caller to eventually free the buffer using a
12583
** call to sqlite3_free().
12584
*/
12585
SQLITE_API int sqlite3changegroup_output(
12586
sqlite3_changegroup*,
12587
int *pnData, /* OUT: Size of output buffer in bytes */
12588
void **ppData /* OUT: Pointer to output buffer */
12589
);
12590
12591
/*
12592
** CAPI3REF: Delete A Changegroup Object
12593
** DESTRUCTOR: sqlite3_changegroup
12594
*/
12595
SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
12596
12597
/*
12598
** CAPI3REF: Apply A Changeset To A Database
12599
**
12600
** Apply a changeset or patchset to a database. These functions attempt to
12601
** update the "main" database attached to handle db with the changes found in
12602
** the changeset passed via the second and third arguments.
12603
**
12604
** All changes made by these functions are enclosed in a savepoint transaction.
12605
** If any other error (aside from a constraint failure when attempting to
12606
** write to the target database) occurs, then the savepoint transaction is
12607
** rolled back, restoring the target database to its original state, and an
12608
** SQLite error code returned. Additionally, starting with version 3.51.0,
12609
** an error code and error message that may be accessed using the
12610
** [sqlite3_errcode()] and [sqlite3_errmsg()] APIs are left in the database
12611
** handle.
12612
**
12613
** The fourth argument (xFilter) passed to these functions is the "filter
12614
** callback". This may be passed NULL, in which case all changes in the
12615
** changeset are applied to the database. For sqlite3changeset_apply() and
12616
** sqlite3_changeset_apply_v2(), if it is not NULL, then it is invoked once
12617
** for each table affected by at least one change in the changeset. In this
12618
** case the table name is passed as the second argument, and a copy of
12619
** the context pointer passed as the sixth argument to apply() or apply_v2()
12620
** as the first. If the "filter callback" returns zero, then no attempt is
12621
** made to apply any changes to the table. Otherwise, if the return value is
12622
** non-zero, all changes related to the table are attempted.
12623
**
12624
** For sqlite3_changeset_apply_v3(), the xFilter callback is invoked once
12625
** per change. The second argument in this case is an sqlite3_changeset_iter
12626
** that may be queried using the usual APIs for the details of the current
12627
** change. If the "filter callback" returns zero in this case, then no attempt
12628
** is made to apply the current change. If it returns non-zero, the change
12629
** is applied.
12630
**
12631
** For each table that is not excluded by the filter callback, this function
12632
** tests that the target database contains a compatible table. A table is
12633
** considered compatible if all of the following are true:
12634
**
12635
** <ul>
12636
** <li> The table has the same name as the name recorded in the
12637
** changeset, and
12638
** <li> The table has at least as many columns as recorded in the
12639
** changeset, and
12640
** <li> The table has primary key columns in the same position as
12641
** recorded in the changeset.
12642
** </ul>
12643
**
12644
** If there is no compatible table, it is not an error, but none of the
12645
** changes associated with the table are applied. A warning message is issued
12646
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
12647
** one such warning is issued for each table in the changeset.
12648
**
12649
** For each change for which there is a compatible table, an attempt is made
12650
** to modify the table contents according to each UPDATE, INSERT or DELETE
12651
** change that is not excluded by a filter callback. If a change cannot be
12652
** applied cleanly, the conflict handler function passed as the fifth argument
12653
** to sqlite3changeset_apply() may be invoked. A description of exactly when
12654
** the conflict handler is invoked for each type of change is below.
12655
**
12656
** Unlike the xFilter argument, xConflict may not be passed NULL. The results
12657
** of passing anything other than a valid function pointer as the xConflict
12658
** argument are undefined.
12659
**
12660
** Each time the conflict handler function is invoked, it must return one
12661
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
12662
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
12663
** if the second argument passed to the conflict handler is either
12664
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
12665
** returns an illegal value, any changes already made are rolled back and
12666
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
12667
** actions are taken by sqlite3changeset_apply() depending on the value
12668
** returned by each invocation of the conflict-handler function. Refer to
12669
** the documentation for the three
12670
** [SQLITE_CHANGESET_OMIT|available return values] for details.
12671
**
12672
** <dl>
12673
** <dt>DELETE Changes<dd>
12674
** For each DELETE change, the function checks if the target database
12675
** contains a row with the same primary key value (or values) as the
12676
** original row values stored in the changeset. If it does, and the values
12677
** stored in all non-primary key columns also match the values stored in
12678
** the changeset the row is deleted from the target database.
12679
**
12680
** If a row with matching primary key values is found, but one or more of
12681
** the non-primary key fields contains a value different from the original
12682
** row value stored in the changeset, the conflict-handler function is
12683
** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
12684
** database table has more columns than are recorded in the changeset,
12685
** only the values of those non-primary key fields are compared against
12686
** the current database contents - any trailing database table columns
12687
** are ignored.
12688
**
12689
** If no row with matching primary key values is found in the database,
12690
** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12691
** passed as the second argument.
12692
**
12693
** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
12694
** (which can only happen if a foreign key constraint is violated), the
12695
** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
12696
** passed as the second argument. This includes the case where the DELETE
12697
** operation is attempted because an earlier call to the conflict handler
12698
** function returned [SQLITE_CHANGESET_REPLACE].
12699
**
12700
** <dt>INSERT Changes<dd>
12701
** For each INSERT change, an attempt is made to insert the new row into
12702
** the database. If the changeset row contains fewer fields than the
12703
** database table, the trailing fields are populated with their default
12704
** values.
12705
**
12706
** If the attempt to insert the row fails because the database already
12707
** contains a row with the same primary key values, the conflict handler
12708
** function is invoked with the second argument set to
12709
** [SQLITE_CHANGESET_CONFLICT].
12710
**
12711
** If the attempt to insert the row fails because of some other constraint
12712
** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
12713
** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
12714
** This includes the case where the INSERT operation is re-attempted because
12715
** an earlier call to the conflict handler function returned
12716
** [SQLITE_CHANGESET_REPLACE].
12717
**
12718
** <dt>UPDATE Changes<dd>
12719
** For each UPDATE change, the function checks if the target database
12720
** contains a row with the same primary key value (or values) as the
12721
** original row values stored in the changeset. If it does, and the values
12722
** stored in all modified non-primary key columns also match the values
12723
** stored in the changeset the row is updated within the target database.
12724
**
12725
** If a row with matching primary key values is found, but one or more of
12726
** the modified non-primary key fields contains a value different from an
12727
** original row value stored in the changeset, the conflict-handler function
12728
** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
12729
** UPDATE changes only contain values for non-primary key fields that are
12730
** to be modified, only those fields need to match the original values to
12731
** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
12732
**
12733
** If no row with matching primary key values is found in the database,
12734
** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12735
** passed as the second argument.
12736
**
12737
** If the UPDATE operation is attempted, but SQLite returns
12738
** SQLITE_CONSTRAINT, the conflict-handler function is invoked with
12739
** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
12740
** This includes the case where the UPDATE operation is attempted after
12741
** an earlier call to the conflict handler function returned
12742
** [SQLITE_CHANGESET_REPLACE].
12743
** </dl>
12744
**
12745
** It is safe to execute SQL statements, including those that write to the
12746
** table that the callback related to, from within the xConflict callback.
12747
** This can be used to further customize the application's conflict
12748
** resolution strategy.
12749
**
12750
** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
12751
** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
12752
** may set (*ppRebase) to point to a "rebase" that may be used with the
12753
** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
12754
** is set to the size of the buffer in bytes. It is the responsibility of the
12755
** caller to eventually free any such buffer using sqlite3_free(). The buffer
12756
** is only allocated and populated if one or more conflicts were encountered
12757
** while applying the patchset. See comments surrounding the sqlite3_rebaser
12758
** APIs for further details.
12759
**
12760
** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
12761
** may be modified by passing a combination of
12762
** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
12763
**
12764
** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
12765
** and therefore subject to change.
12766
*/
12767
SQLITE_API int sqlite3changeset_apply(
12768
sqlite3 *db, /* Apply change to "main" db of this handle */
12769
int nChangeset, /* Size of changeset in bytes */
12770
void *pChangeset, /* Changeset blob */
12771
int(*xFilter)(
12772
void *pCtx, /* Copy of sixth arg to _apply() */
12773
const char *zTab /* Table name */
12774
),
12775
int(*xConflict)(
12776
void *pCtx, /* Copy of sixth arg to _apply() */
12777
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
12778
sqlite3_changeset_iter *p /* Handle describing change and conflict */
12779
),
12780
void *pCtx /* First argument passed to xConflict */
12781
);
12782
SQLITE_API int sqlite3changeset_apply_v2(
12783
sqlite3 *db, /* Apply change to "main" db of this handle */
12784
int nChangeset, /* Size of changeset in bytes */
12785
void *pChangeset, /* Changeset blob */
12786
int(*xFilter)(
12787
void *pCtx, /* Copy of sixth arg to _apply() */
12788
const char *zTab /* Table name */
12789
),
12790
int(*xConflict)(
12791
void *pCtx, /* Copy of sixth arg to _apply() */
12792
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
12793
sqlite3_changeset_iter *p /* Handle describing change and conflict */
12794
),
12795
void *pCtx, /* First argument passed to xConflict */
12796
void **ppRebase, int *pnRebase, /* OUT: Rebase data */
12797
int flags /* SESSION_CHANGESETAPPLY_* flags */
12798
);
12799
SQLITE_API int sqlite3changeset_apply_v3(
12800
sqlite3 *db, /* Apply change to "main" db of this handle */
12801
int nChangeset, /* Size of changeset in bytes */
12802
void *pChangeset, /* Changeset blob */
12803
int(*xFilter)(
12804
void *pCtx, /* Copy of sixth arg to _apply() */
12805
sqlite3_changeset_iter *p /* Handle describing change */
12806
),
12807
int(*xConflict)(
12808
void *pCtx, /* Copy of sixth arg to _apply() */
12809
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
12810
sqlite3_changeset_iter *p /* Handle describing change and conflict */
12811
),
12812
void *pCtx, /* First argument passed to xConflict */
12813
void **ppRebase, int *pnRebase, /* OUT: Rebase data */
12814
int flags /* SESSION_CHANGESETAPPLY_* flags */
12815
);
12816
12817
/*
12818
** CAPI3REF: Flags for sqlite3changeset_apply_v2
12819
**
12820
** The following flags may passed via the 9th parameter to
12821
** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
12822
**
12823
** <dl>
12824
** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
12825
** Usually, the sessions module encloses all operations performed by
12826
** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
12827
** SAVEPOINT is committed if the changeset or patchset is successfully
12828
** applied, or rolled back if an error occurs. Specifying this flag
12829
** causes the sessions module to omit this savepoint. In this case, if the
12830
** caller has an open transaction or savepoint when apply_v2() is called,
12831
** it may revert the partially applied changeset by rolling it back.
12832
**
12833
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
12834
** Invert the changeset before applying it. This is equivalent to inverting
12835
** a changeset using sqlite3changeset_invert() before applying it. It is
12836
** an error to specify this flag with a patchset.
12837
**
12838
** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd>
12839
** Do not invoke the conflict handler callback for any changes that
12840
** would not actually modify the database even if they were applied.
12841
** Specifically, this means that the conflict handler is not invoked
12842
** for:
12843
** <ul>
12844
** <li>a delete change if the row being deleted cannot be found,
12845
** <li>an update change if the modified fields are already set to
12846
** their new values in the conflicting row, or
12847
** <li>an insert change if all fields of the conflicting row match
12848
** the row being inserted.
12849
** </ul>
12850
**
12851
** <dt>SQLITE_CHANGESETAPPLY_FKNOACTION <dd>
12852
** If this flag it set, then all foreign key constraints in the target
12853
** database behave as if they were declared with "ON UPDATE NO ACTION ON
12854
** DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL
12855
** or SET DEFAULT.
12856
*/
12857
#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001
12858
#define SQLITE_CHANGESETAPPLY_INVERT 0x0002
12859
#define SQLITE_CHANGESETAPPLY_IGNORENOOP 0x0004
12860
#define SQLITE_CHANGESETAPPLY_FKNOACTION 0x0008
12861
12862
/*
12863
** CAPI3REF: Constants Passed To The Conflict Handler
12864
**
12865
** Values that may be passed as the second argument to a conflict-handler.
12866
**
12867
** <dl>
12868
** <dt>SQLITE_CHANGESET_DATA<dd>
12869
** The conflict handler is invoked with CHANGESET_DATA as the second argument
12870
** when processing a DELETE or UPDATE change if a row with the required
12871
** PRIMARY KEY fields is present in the database, but one or more other
12872
** (non primary-key) fields modified by the update do not contain the
12873
** expected "before" values.
12874
**
12875
** The conflicting row, in this case, is the database row with the matching
12876
** primary key.
12877
**
12878
** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
12879
** The conflict handler is invoked with CHANGESET_NOTFOUND as the second
12880
** argument when processing a DELETE or UPDATE change if a row with the
12881
** required PRIMARY KEY fields is not present in the database.
12882
**
12883
** There is no conflicting row in this case. The results of invoking the
12884
** sqlite3changeset_conflict() API are undefined.
12885
**
12886
** <dt>SQLITE_CHANGESET_CONFLICT<dd>
12887
** CHANGESET_CONFLICT is passed as the second argument to the conflict
12888
** handler while processing an INSERT change if the operation would result
12889
** in duplicate primary key values.
12890
**
12891
** The conflicting row in this case is the database row with the matching
12892
** primary key.
12893
**
12894
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
12895
** If foreign key handling is enabled, and applying a changeset leaves the
12896
** database in a state containing foreign key violations, the conflict
12897
** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
12898
** exactly once before the changeset is committed. If the conflict handler
12899
** returns CHANGESET_OMIT, the changes, including those that caused the
12900
** foreign key constraint violation, are committed. Or, if it returns
12901
** CHANGESET_ABORT, the changeset is rolled back.
12902
**
12903
** No current or conflicting row information is provided. The only function
12904
** it is possible to call on the supplied sqlite3_changeset_iter handle
12905
** is sqlite3changeset_fk_conflicts().
12906
**
12907
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
12908
** If any other constraint violation occurs while applying a change (i.e.
12909
** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
12910
** invoked with CHANGESET_CONSTRAINT as the second argument.
12911
**
12912
** There is no conflicting row in this case. The results of invoking the
12913
** sqlite3changeset_conflict() API are undefined.
12914
**
12915
** </dl>
12916
*/
12917
#define SQLITE_CHANGESET_DATA 1
12918
#define SQLITE_CHANGESET_NOTFOUND 2
12919
#define SQLITE_CHANGESET_CONFLICT 3
12920
#define SQLITE_CHANGESET_CONSTRAINT 4
12921
#define SQLITE_CHANGESET_FOREIGN_KEY 5
12922
12923
/*
12924
** CAPI3REF: Constants Returned By The Conflict Handler
12925
**
12926
** A conflict handler callback must return one of the following three values.
12927
**
12928
** <dl>
12929
** <dt>SQLITE_CHANGESET_OMIT<dd>
12930
** If a conflict handler returns this value no special action is taken. The
12931
** change that caused the conflict is not applied. The session module
12932
** continues to the next change in the changeset.
12933
**
12934
** <dt>SQLITE_CHANGESET_REPLACE<dd>
12935
** This value may only be returned if the second argument to the conflict
12936
** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
12937
** is not the case, any changes applied so far are rolled back and the
12938
** call to sqlite3changeset_apply() returns SQLITE_MISUSE.
12939
**
12940
** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
12941
** handler, then the conflicting row is either updated or deleted, depending
12942
** on the type of change.
12943
**
12944
** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
12945
** handler, then the conflicting row is removed from the database and a
12946
** second attempt to apply the change is made. If this second attempt fails,
12947
** the original row is restored to the database before continuing.
12948
**
12949
** <dt>SQLITE_CHANGESET_ABORT<dd>
12950
** If this value is returned, any changes applied so far are rolled back
12951
** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
12952
** </dl>
12953
*/
12954
#define SQLITE_CHANGESET_OMIT 0
12955
#define SQLITE_CHANGESET_REPLACE 1
12956
#define SQLITE_CHANGESET_ABORT 2
12957
12958
/*
12959
** CAPI3REF: Rebasing changesets
12960
** EXPERIMENTAL
12961
**
12962
** Suppose there is a site hosting a database in state S0. And that
12963
** modifications are made that move that database to state S1 and a
12964
** changeset recorded (the "local" changeset). Then, a changeset based
12965
** on S0 is received from another site (the "remote" changeset) and
12966
** applied to the database. The database is then in state
12967
** (S1+"remote"), where the exact state depends on any conflict
12968
** resolution decisions (OMIT or REPLACE) made while applying "remote".
12969
** Rebasing a changeset is to update it to take those conflict
12970
** resolution decisions into account, so that the same conflicts
12971
** do not have to be resolved elsewhere in the network.
12972
**
12973
** For example, if both the local and remote changesets contain an
12974
** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
12975
**
12976
** local: INSERT INTO t1 VALUES(1, 'v1');
12977
** remote: INSERT INTO t1 VALUES(1, 'v2');
12978
**
12979
** and the conflict resolution is REPLACE, then the INSERT change is
12980
** removed from the local changeset (it was overridden). Or, if the
12981
** conflict resolution was "OMIT", then the local changeset is modified
12982
** to instead contain:
12983
**
12984
** UPDATE t1 SET b = 'v2' WHERE a=1;
12985
**
12986
** Changes within the local changeset are rebased as follows:
12987
**
12988
** <dl>
12989
** <dt>Local INSERT<dd>
12990
** This may only conflict with a remote INSERT. If the conflict
12991
** resolution was OMIT, then add an UPDATE change to the rebased
12992
** changeset. Or, if the conflict resolution was REPLACE, add
12993
** nothing to the rebased changeset.
12994
**
12995
** <dt>Local DELETE<dd>
12996
** This may conflict with a remote UPDATE or DELETE. In both cases the
12997
** only possible resolution is OMIT. If the remote operation was a
12998
** DELETE, then add no change to the rebased changeset. If the remote
12999
** operation was an UPDATE, then the old.* fields of change are updated
13000
** to reflect the new.* values in the UPDATE.
13001
**
13002
** <dt>Local UPDATE<dd>
13003
** This may conflict with a remote UPDATE or DELETE. If it conflicts
13004
** with a DELETE, and the conflict resolution was OMIT, then the update
13005
** is changed into an INSERT. Any undefined values in the new.* record
13006
** from the update change are filled in using the old.* values from
13007
** the conflicting DELETE. Or, if the conflict resolution was REPLACE,
13008
** the UPDATE change is simply omitted from the rebased changeset.
13009
**
13010
** If conflict is with a remote UPDATE and the resolution is OMIT, then
13011
** the old.* values are rebased using the new.* values in the remote
13012
** change. Or, if the resolution is REPLACE, then the change is copied
13013
** into the rebased changeset with updates to columns also updated by
13014
** the conflicting remote UPDATE removed. If this means no columns would
13015
** be updated, the change is omitted.
13016
** </dl>
13017
**
13018
** A local change may be rebased against multiple remote changes
13019
** simultaneously. If a single key is modified by multiple remote
13020
** changesets, they are combined as follows before the local changeset
13021
** is rebased:
13022
**
13023
** <ul>
13024
** <li> If there has been one or more REPLACE resolutions on a
13025
** key, it is rebased according to a REPLACE.
13026
**
13027
** <li> If there have been no REPLACE resolutions on a key, then
13028
** the local changeset is rebased according to the most recent
13029
** of the OMIT resolutions.
13030
** </ul>
13031
**
13032
** Note that conflict resolutions from multiple remote changesets are
13033
** combined on a per-field basis, not per-row. This means that in the
13034
** case of multiple remote UPDATE operations, some fields of a single
13035
** local change may be rebased for REPLACE while others are rebased for
13036
** OMIT.
13037
**
13038
** In order to rebase a local changeset, the remote changeset must first
13039
** be applied to the local database using sqlite3changeset_apply_v2() and
13040
** the buffer of rebase information captured. Then:
13041
**
13042
** <ol>
13043
** <li> An sqlite3_rebaser object is created by calling
13044
** sqlite3rebaser_create().
13045
** <li> The new object is configured with the rebase buffer obtained from
13046
** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
13047
** If the local changeset is to be rebased against multiple remote
13048
** changesets, then sqlite3rebaser_configure() should be called
13049
** multiple times, in the same order that the multiple
13050
** sqlite3changeset_apply_v2() calls were made.
13051
** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
13052
** <li> The sqlite3_rebaser object is deleted by calling
13053
** sqlite3rebaser_delete().
13054
** </ol>
13055
*/
13056
typedef struct sqlite3_rebaser sqlite3_rebaser;
13057
13058
/*
13059
** CAPI3REF: Create a changeset rebaser object.
13060
** EXPERIMENTAL
13061
**
13062
** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
13063
** point to the new object and return SQLITE_OK. Otherwise, if an error
13064
** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
13065
** to NULL.
13066
*/
13067
SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
13068
13069
/*
13070
** CAPI3REF: Configure a changeset rebaser object.
13071
** EXPERIMENTAL
13072
**
13073
** Configure the changeset rebaser object to rebase changesets according
13074
** to the conflict resolutions described by buffer pRebase (size nRebase
13075
** bytes), which must have been obtained from a previous call to
13076
** sqlite3changeset_apply_v2().
13077
*/
13078
SQLITE_API int sqlite3rebaser_configure(
13079
sqlite3_rebaser*,
13080
int nRebase, const void *pRebase
13081
);
13082
13083
/*
13084
** CAPI3REF: Rebase a changeset
13085
** EXPERIMENTAL
13086
**
13087
** Argument pIn must point to a buffer containing a changeset nIn bytes
13088
** in size. This function allocates and populates a buffer with a copy
13089
** of the changeset rebased according to the configuration of the
13090
** rebaser object passed as the first argument. If successful, (*ppOut)
13091
** is set to point to the new buffer containing the rebased changeset and
13092
** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
13093
** responsibility of the caller to eventually free the new buffer using
13094
** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
13095
** are set to zero and an SQLite error code returned.
13096
*/
13097
SQLITE_API int sqlite3rebaser_rebase(
13098
sqlite3_rebaser*,
13099
int nIn, const void *pIn,
13100
int *pnOut, void **ppOut
13101
);
13102
13103
/*
13104
** CAPI3REF: Delete a changeset rebaser object.
13105
** EXPERIMENTAL
13106
**
13107
** Delete the changeset rebaser object and all associated resources. There
13108
** should be one call to this function for each successful invocation
13109
** of sqlite3rebaser_create().
13110
*/
13111
SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
13112
13113
/*
13114
** CAPI3REF: Streaming Versions of API functions.
13115
**
13116
** The six streaming API xxx_strm() functions serve similar purposes to the
13117
** corresponding non-streaming API functions:
13118
**
13119
** <table border=1 style="margin-left:8ex;margin-right:8ex">
13120
** <tr><th>Streaming function<th>Non-streaming equivalent</th>
13121
** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
13122
** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
13123
** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
13124
** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
13125
** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
13126
** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
13127
** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
13128
** </table>
13129
**
13130
** Non-streaming functions that accept changesets (or patchsets) as input
13131
** require that the entire changeset be stored in a single buffer in memory.
13132
** Similarly, those that return a changeset or patchset do so by returning
13133
** a pointer to a single large buffer allocated using sqlite3_malloc().
13134
** Normally this is convenient. However, if an application running in a
13135
** low-memory environment is required to handle very large changesets, the
13136
** large contiguous memory allocations required can become onerous.
13137
**
13138
** In order to avoid this problem, instead of a single large buffer, input
13139
** is passed to a streaming API functions by way of a callback function that
13140
** the sessions module invokes to incrementally request input data as it is
13141
** required. In all cases, a pair of API function parameters such as
13142
**
13143
** <pre>
13144
** &nbsp; int nChangeset,
13145
** &nbsp; void *pChangeset,
13146
** </pre>
13147
**
13148
** Is replaced by:
13149
**
13150
** <pre>
13151
** &nbsp; int (*xInput)(void *pIn, void *pData, int *pnData),
13152
** &nbsp; void *pIn,
13153
** </pre>
13154
**
13155
** Each time the xInput callback is invoked by the sessions module, the first
13156
** argument passed is a copy of the supplied pIn context pointer. The second
13157
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
13158
** error occurs the xInput method should copy up to (*pnData) bytes of data
13159
** into the buffer and set (*pnData) to the actual number of bytes copied
13160
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
13161
** should be set to zero to indicate this. Or, if an error occurs, an SQLite
13162
** error code should be returned. In all cases, if an xInput callback returns
13163
** an error, all processing is abandoned and the streaming API function
13164
** returns a copy of the error code to the caller.
13165
**
13166
** In the case of sqlite3changeset_start_strm(), the xInput callback may be
13167
** invoked by the sessions module at any point during the lifetime of the
13168
** iterator. If such an xInput callback returns an error, the iterator enters
13169
** an error state, whereby all subsequent calls to iterator functions
13170
** immediately fail with the same error code as returned by xInput.
13171
**
13172
** Similarly, streaming API functions that return changesets (or patchsets)
13173
** return them in chunks by way of a callback function instead of via a
13174
** pointer to a single large buffer. In this case, a pair of parameters such
13175
** as:
13176
**
13177
** <pre>
13178
** &nbsp; int *pnChangeset,
13179
** &nbsp; void **ppChangeset,
13180
** </pre>
13181
**
13182
** Is replaced by:
13183
**
13184
** <pre>
13185
** &nbsp; int (*xOutput)(void *pOut, const void *pData, int nData),
13186
** &nbsp; void *pOut
13187
** </pre>
13188
**
13189
** The xOutput callback is invoked zero or more times to return data to
13190
** the application. The first parameter passed to each call is a copy of the
13191
** pOut pointer supplied by the application. The second parameter, pData,
13192
** points to a buffer nData bytes in size containing the chunk of output
13193
** data being returned. If the xOutput callback successfully processes the
13194
** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
13195
** it should return some other SQLite error code. In this case processing
13196
** is immediately abandoned and the streaming API function returns a copy
13197
** of the xOutput error code to the application.
13198
**
13199
** The sessions module never invokes an xOutput callback with the third
13200
** parameter set to a value less than or equal to zero. Other than this,
13201
** no guarantees are made as to the size of the chunks of data returned.
13202
*/
13203
SQLITE_API int sqlite3changeset_apply_strm(
13204
sqlite3 *db, /* Apply change to "main" db of this handle */
13205
int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
13206
void *pIn, /* First arg for xInput */
13207
int(*xFilter)(
13208
void *pCtx, /* Copy of sixth arg to _apply() */
13209
const char *zTab /* Table name */
13210
),
13211
int(*xConflict)(
13212
void *pCtx, /* Copy of sixth arg to _apply() */
13213
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
13214
sqlite3_changeset_iter *p /* Handle describing change and conflict */
13215
),
13216
void *pCtx /* First argument passed to xConflict */
13217
);
13218
SQLITE_API int sqlite3changeset_apply_v2_strm(
13219
sqlite3 *db, /* Apply change to "main" db of this handle */
13220
int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
13221
void *pIn, /* First arg for xInput */
13222
int(*xFilter)(
13223
void *pCtx, /* Copy of sixth arg to _apply() */
13224
const char *zTab /* Table name */
13225
),
13226
int(*xConflict)(
13227
void *pCtx, /* Copy of sixth arg to _apply() */
13228
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
13229
sqlite3_changeset_iter *p /* Handle describing change and conflict */
13230
),
13231
void *pCtx, /* First argument passed to xConflict */
13232
void **ppRebase, int *pnRebase,
13233
int flags
13234
);
13235
SQLITE_API int sqlite3changeset_apply_v3_strm(
13236
sqlite3 *db, /* Apply change to "main" db of this handle */
13237
int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
13238
void *pIn, /* First arg for xInput */
13239
int(*xFilter)(
13240
void *pCtx, /* Copy of sixth arg to _apply() */
13241
sqlite3_changeset_iter *p
13242
),
13243
int(*xConflict)(
13244
void *pCtx, /* Copy of sixth arg to _apply() */
13245
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */
13246
sqlite3_changeset_iter *p /* Handle describing change and conflict */
13247
),
13248
void *pCtx, /* First argument passed to xConflict */
13249
void **ppRebase, int *pnRebase,
13250
int flags
13251
);
13252
SQLITE_API int sqlite3changeset_concat_strm(
13253
int (*xInputA)(void *pIn, void *pData, int *pnData),
13254
void *pInA,
13255
int (*xInputB)(void *pIn, void *pData, int *pnData),
13256
void *pInB,
13257
int (*xOutput)(void *pOut, const void *pData, int nData),
13258
void *pOut
13259
);
13260
SQLITE_API int sqlite3changeset_invert_strm(
13261
int (*xInput)(void *pIn, void *pData, int *pnData),
13262
void *pIn,
13263
int (*xOutput)(void *pOut, const void *pData, int nData),
13264
void *pOut
13265
);
13266
SQLITE_API int sqlite3changeset_start_strm(
13267
sqlite3_changeset_iter **pp,
13268
int (*xInput)(void *pIn, void *pData, int *pnData),
13269
void *pIn
13270
);
13271
SQLITE_API int sqlite3changeset_start_v2_strm(
13272
sqlite3_changeset_iter **pp,
13273
int (*xInput)(void *pIn, void *pData, int *pnData),
13274
void *pIn,
13275
int flags
13276
);
13277
SQLITE_API int sqlite3session_changeset_strm(
13278
sqlite3_session *pSession,
13279
int (*xOutput)(void *pOut, const void *pData, int nData),
13280
void *pOut
13281
);
13282
SQLITE_API int sqlite3session_patchset_strm(
13283
sqlite3_session *pSession,
13284
int (*xOutput)(void *pOut, const void *pData, int nData),
13285
void *pOut
13286
);
13287
SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
13288
int (*xInput)(void *pIn, void *pData, int *pnData),
13289
void *pIn
13290
);
13291
SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
13292
int (*xOutput)(void *pOut, const void *pData, int nData),
13293
void *pOut
13294
);
13295
SQLITE_API int sqlite3rebaser_rebase_strm(
13296
sqlite3_rebaser *pRebaser,
13297
int (*xInput)(void *pIn, void *pData, int *pnData),
13298
void *pIn,
13299
int (*xOutput)(void *pOut, const void *pData, int nData),
13300
void *pOut
13301
);
13302
13303
/*
13304
** CAPI3REF: Configure global parameters
13305
**
13306
** The sqlite3session_config() interface is used to make global configuration
13307
** changes to the sessions module in order to tune it to the specific needs
13308
** of the application.
13309
**
13310
** The sqlite3session_config() interface is not threadsafe. If it is invoked
13311
** while any other thread is inside any other sessions method then the
13312
** results are undefined. Furthermore, if it is invoked after any sessions
13313
** related objects have been created, the results are also undefined.
13314
**
13315
** The first argument to the sqlite3session_config() function must be one
13316
** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
13317
** interpretation of the (void*) value passed as the second parameter and
13318
** the effect of calling this function depends on the value of the first
13319
** parameter.
13320
**
13321
** <dl>
13322
** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
13323
** By default, the sessions module streaming interfaces attempt to input
13324
** and output data in approximately 1 KiB chunks. This operand may be used
13325
** to set and query the value of this configuration setting. The pointer
13326
** passed as the second argument must point to a value of type (int).
13327
** If this value is greater than 0, it is used as the new streaming data
13328
** chunk size for both input and output. Before returning, the (int) value
13329
** pointed to by pArg is set to the final value of the streaming interface
13330
** chunk size.
13331
** </dl>
13332
**
13333
** This function returns SQLITE_OK if successful, or an SQLite error code
13334
** otherwise.
13335
*/
13336
SQLITE_API int sqlite3session_config(int op, void *pArg);
13337
13338
/*
13339
** CAPI3REF: Values for sqlite3session_config().
13340
*/
13341
#define SQLITE_SESSION_CONFIG_STRMSIZE 1
13342
13343
/*
13344
** CAPI3REF: Configure a changegroup object
13345
**
13346
** Configure the changegroup object passed as the first argument.
13347
** At present the only valid value for the second parameter is
13348
** [SQLITE_CHANGEGROUP_CONFIG_PATCHSET].
13349
*/
13350
SQLITE_API int sqlite3changegroup_config(sqlite3_changegroup*, int, void *pArg);
13351
13352
/*
13353
** CAPI3REF: Options for sqlite3changegroup_config().
13354
**
13355
** The following values may be passed as the 2nd parameter to
13356
** sqlite3changegroup_config().
13357
**
13358
** <dt>SQLITE_CHANGEGROUP_CONFIG_PATCHSET <dd>
13359
** A changegroup object generates either a changeset or patchset. Usually,
13360
** this is determined by whether the first call to sqlite3changegroup_add()
13361
** is passed a changeset or a patchset. Or, if the first changes are added
13362
** to the changegroup object using the sqlite3changegroup_change_xxx()
13363
** APIs, then this option may be used to configure whether the changegroup
13364
** object generates a changeset or patchset.
13365
**
13366
** When this option is invoked, parameter pArg must point to a value of
13367
** type int. If the changegroup currently contains zero changes, and the
13368
** value of the int variable is zero or greater than zero, then the
13369
** changegroup is configured to generate a changeset or patchset,
13370
** respectively. It is a no-op, not an error, if the changegroup is not
13371
** configured because it has already started accumulating changes.
13372
**
13373
** Before returning, the int variable is set to 0 if the changegroup is
13374
** configured to generate a changeset, or 1 if it is configured to generate
13375
** a patchset.
13376
*/
13377
#define SQLITE_CHANGEGROUP_CONFIG_PATCHSET 1
13378
13379
13380
/*
13381
** CAPI3REF: Begin adding a change to a changegroup
13382
**
13383
** This API is used, in concert with other sqlite3changegroup_change_xxx()
13384
** APIs, to add changes to a changegroup object one at a time. To add a
13385
** single change, the caller must:
13386
**
13387
** 1. Invoke sqlite3changegroup_change_begin() to indicate the type of
13388
** change (INSERT, UPDATE or DELETE), the affected table and whether
13389
** or not the change should be marked as indirect.
13390
**
13391
** 2. Invoke sqlite3changegroup_change_int64() or one of the other four
13392
** value functions - _null(), _double(), _text() or _blob() - one or
13393
** more times to specify old.* and new.* values for the change being
13394
** constructed.
13395
**
13396
** 3. Invoke sqlite3changegroup_change_finish() to either finish adding
13397
** the change to the group, or to discard the change altogether.
13398
**
13399
** The first argument to this function must be a pointer to the existing
13400
** changegroup object that the change will be added to. The second argument
13401
** must be SQLITE_INSERT, SQLITE_UPDATE or SQLITE_DELETE. The third is the
13402
** name of the table that the change affects, and the fourth is a boolean
13403
** flag specifying whether the change should be marked as "indirect" (if
13404
** bIndirect is non-zero) or not indirect (if bIndirect is zero).
13405
**
13406
** Following a successful call to this function, this function may not be
13407
** called again on the same changegroup object until after
13408
** sqlite3changegroup_change_finish() has been called. Doing so is an
13409
** SQLITE_MISUSE error.
13410
**
13411
** The changegroup object passed as the first argument must be already
13412
** configured with schema data for the specified table. It may be configured
13413
** either by calling sqlite3changegroup_schema() with a database that contains
13414
** the table, or sqlite3changegroup_add() with a changeset that contains the
13415
** table. If the changegroup object has not been configured with a schema for
13416
** the specified table when this function is called, SQLITE_ERROR is returned.
13417
**
13418
** If successful, SQLITE_OK is returned. Otherwise, if an error occurs, an
13419
** SQLite error code is returned. In this case, if argument pzErr is non-NULL,
13420
** then (*pzErr) may be set to point to a buffer containing a utf-8 formated,
13421
** nul-terminated, English language error message. It is the responsibility
13422
** of the caller to eventually free this buffer using sqlite3_free().
13423
*/
13424
SQLITE_API int sqlite3changegroup_change_begin(
13425
sqlite3_changegroup*,
13426
int eOp,
13427
const char *zTab,
13428
int bIndirect,
13429
char **pzErr
13430
);
13431
13432
/*
13433
** CAPI3REF: Add a 64-bit integer to a changegroup
13434
**
13435
** This function may only be called between a successful call to
13436
** sqlite3changegroup_change_begin() and its matching
13437
** sqlite3changegroup_change_finish() call. If it is called at any
13438
** other time, it is an SQLITE_MISUSE error. Calling this function
13439
** specifies a 64-bit integer value to be used in the change currently being
13440
** added to the changegroup object passed as the first argument.
13441
**
13442
** The second parameter, bNew, specifies whether the value is to be part of
13443
** the new.* (if bNew is non-zero) or old.* (if bNew is zero) record of
13444
** the change under construction. If this does not match the type of change
13445
** specified by the preceding call to sqlite3changegroup_change_begin() (i.e.
13446
** an old.* value for an SQLITE_INSERT change, or a new.* value for an
13447
** SQLITE_DELETE), then SQLITE_ERROR is returned.
13448
**
13449
** The third parameter specifies the column of the old.* or new.* record that
13450
** the value will be a part of. If the specified table has an explicit primary
13451
** key, then this is the index of the table column, numbered from 0 in the order
13452
** specified within the CREATE TABLE statement. Or, if the table uses an
13453
** implicit rowid key, then the column 0 is the rowid and the explicit columns
13454
** are numbered starting from 1. If the iCol parameter is less than 0 or greater
13455
** than the index of the last column in the table, SQLITE_RANGE is returned.
13456
**
13457
** The fourth parameter is the integer value to use as part of the old.* or
13458
** new.* record.
13459
**
13460
** If this call is successful, SQLITE_OK is returned. Otherwise, if an
13461
** error occurs, an SQLite error code is returned.
13462
*/
13463
SQLITE_API int sqlite3changegroup_change_int64(
13464
sqlite3_changegroup*,
13465
int bNew,
13466
int iCol,
13467
sqlite3_int64 iVal
13468
);
13469
13470
/*
13471
** CAPI3REF: Add a NULL to a changegroup
13472
**
13473
** This function is similar to sqlite3changegroup_change_int64(). Except that
13474
** it configures the change currently under construction with a NULL value
13475
** instead of a 64-bit integer.
13476
*/
13477
SQLITE_API int sqlite3changegroup_change_null(sqlite3_changegroup*, int, int);
13478
13479
/*
13480
** CAPI3REF: Add an double to a changegroup
13481
**
13482
** This function is similar to sqlite3changegroup_change_int64(). Except that
13483
** it configures the change currently being constructed with a real value
13484
** instead of a 64-bit integer.
13485
*/
13486
SQLITE_API int sqlite3changegroup_change_double(sqlite3_changegroup*, int, int, double);
13487
13488
/*
13489
** CAPI3REF: Add a text value to a changegroup
13490
**
13491
** This function is similar to sqlite3changegroup_change_int64(). It configures
13492
** the currently accumulated change with a text value instead of a 64-bit
13493
** integer. Parameter pVal points to a buffer containing the text encoded using
13494
** utf-8. Parameter nVal may either be the size of the text value in bytes, or
13495
** else a negative value, in which case the buffer pVal points to is assumed to
13496
** be nul-terminated.
13497
*/
13498
SQLITE_API int sqlite3changegroup_change_text(
13499
sqlite3_changegroup*, int, int, const char *pVal, int nVal
13500
);
13501
13502
/*
13503
** CAPI3REF: Add a blob to a changegroup
13504
**
13505
** This function is similar to sqlite3changegroup_change_int64(). It configures
13506
** the currently accumulated change with a blob value instead of a 64-bit
13507
** integer. Parameter pVal points to a buffer containing the blob. Parameter
13508
** nVal is the size of the blob in bytes.
13509
*/
13510
SQLITE_API int sqlite3changegroup_change_blob(
13511
sqlite3_changegroup*, int, int, const void *pVal, int nVal
13512
);
13513
13514
/*
13515
** CAPI3REF: Finish adding one-at-at-time changes to a changegroup
13516
**
13517
** This function may only be called following a successful call to
13518
** sqlite3changegroup_change_begin(). Otherwise, it is an SQLITE_MISUSE error.
13519
**
13520
** If parameter bDiscard is non-zero, then the current change is simply
13521
** discarded. In this case this function is always successful and SQLITE_OK
13522
** returned.
13523
**
13524
** If parameter bDiscard is zero, then an attempt is made to add the current
13525
** change to the changegroup. Assuming the changegroup is configured to
13526
** produce a changeset (not a patchset), this requires that:
13527
**
13528
** * If the change is an INSERT or DELETE, then a value must be specified
13529
** for all columns of the new.* or old.* record, respectively.
13530
**
13531
** * If the change is an UPDATE record, then values must be provided for
13532
** the PRIMARY KEY columns of the old.* record, but must not be provided
13533
** for PRIMARY KEY columns of the new.* record.
13534
**
13535
** * If the change is an UPDATE record, then for each non-PRIMARY KEY
13536
** column in the old.* record for which a value has been provided, a
13537
** value must also be provided for the same column in the new.* record.
13538
** Similarly, for each non-PK column in the old.* record for which
13539
** a value is not provided, a value must not be provided for the same
13540
** column in the new.* record.
13541
**
13542
** * All values specified for PRIMARY KEY columns must be non-NULL.
13543
**
13544
** Otherwise, it is an error.
13545
**
13546
** If the changegroup already contains a change for the same row (identified
13547
** by PRIMARY KEY columns), then the current change is combined with the
13548
** existing change in the same way as for sqlite3changegroup_add().
13549
**
13550
** For a patchset, all of the above rules apply except that it doesn't matter
13551
** whether or not values are provided for the non-PK old.* record columns
13552
** for an UPDATE or DELETE change. This means that code used to produce
13553
** a changeset using the sqlite3changegroup_change_xxx() APIs may also
13554
** be used to produce patchsets.
13555
**
13556
** If the call is successful, SQLITE_OK is returned. Otherwise, if an error
13557
** occurs, an SQLite error code is returned. If an error is returned and
13558
** parameter pzErr is not NULL, then (*pzErr) may be set to point to a buffer
13559
** containing a nul-terminated, utf-8 encoded, English language error message.
13560
** It is the responsibility of the caller to eventually free any such error
13561
** message buffer using sqlite3_free().
13562
*/
13563
SQLITE_API int sqlite3changegroup_change_finish(
13564
sqlite3_changegroup*,
13565
int bDiscard,
13566
char **pzErr
13567
);
13568
13569
/*
13570
** Make sure we can call this stuff from C++.
13571
*/
13572
#ifdef __cplusplus
13573
}
13574
#endif
13575
13576
#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
13577
13578
/******** End of sqlite3session.h *********/
13579
/******** Begin file fts5.h *********/
13580
/*
13581
** 2014 May 31
13582
**
13583
** The author disclaims copyright to this source code. In place of
13584
** a legal notice, here is a blessing:
13585
**
13586
** May you do good and not evil.
13587
** May you find forgiveness for yourself and forgive others.
13588
** May you share freely, never taking more than you give.
13589
**
13590
******************************************************************************
13591
**
13592
** Interfaces to extend FTS5. Using the interfaces defined in this file,
13593
** FTS5 may be extended with:
13594
**
13595
** * custom tokenizers, and
13596
** * custom auxiliary functions.
13597
*/
13598
13599
13600
#ifndef _FTS5_H
13601
#define _FTS5_H
13602
13603
13604
#ifdef __cplusplus
13605
extern "C" {
13606
#endif
13607
13608
/*************************************************************************
13609
** CUSTOM AUXILIARY FUNCTIONS
13610
**
13611
** Virtual table implementations may overload SQL functions by implementing
13612
** the sqlite3_module.xFindFunction() method.
13613
*/
13614
13615
typedef struct Fts5ExtensionApi Fts5ExtensionApi;
13616
typedef struct Fts5Context Fts5Context;
13617
typedef struct Fts5PhraseIter Fts5PhraseIter;
13618
13619
typedef void (*fts5_extension_function)(
13620
const Fts5ExtensionApi *pApi, /* API offered by current FTS version */
13621
Fts5Context *pFts, /* First arg to pass to pApi functions */
13622
sqlite3_context *pCtx, /* Context for returning result/error */
13623
int nVal, /* Number of values in apVal[] array */
13624
sqlite3_value **apVal /* Array of trailing arguments */
13625
);
13626
13627
struct Fts5PhraseIter {
13628
const unsigned char *a;
13629
const unsigned char *b;
13630
};
13631
13632
/*
13633
** EXTENSION API FUNCTIONS
13634
**
13635
** xUserData(pFts):
13636
** Return a copy of the pUserData pointer passed to the xCreateFunction()
13637
** API when the extension function was registered.
13638
**
13639
** xColumnTotalSize(pFts, iCol, pnToken):
13640
** If parameter iCol is less than zero, set output variable *pnToken
13641
** to the total number of tokens in the FTS5 table. Or, if iCol is
13642
** non-negative but less than the number of columns in the table, return
13643
** the total number of tokens in column iCol, considering all rows in
13644
** the FTS5 table.
13645
**
13646
** If parameter iCol is greater than or equal to the number of columns
13647
** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
13648
** an OOM condition or IO error), an appropriate SQLite error code is
13649
** returned.
13650
**
13651
** xColumnCount(pFts):
13652
** Return the number of columns in the table.
13653
**
13654
** xColumnSize(pFts, iCol, pnToken):
13655
** If parameter iCol is less than zero, set output variable *pnToken
13656
** to the total number of tokens in the current row. Or, if iCol is
13657
** non-negative but less than the number of columns in the table, set
13658
** *pnToken to the number of tokens in column iCol of the current row.
13659
**
13660
** If parameter iCol is greater than or equal to the number of columns
13661
** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
13662
** an OOM condition or IO error), an appropriate SQLite error code is
13663
** returned.
13664
**
13665
** This function may be quite inefficient if used with an FTS5 table
13666
** created with the "columnsize=0" option.
13667
**
13668
** xColumnText:
13669
** If parameter iCol is less than zero, or greater than or equal to the
13670
** number of columns in the table, SQLITE_RANGE is returned.
13671
**
13672
** Otherwise, this function attempts to retrieve the text of column iCol of
13673
** the current document. If successful, (*pz) is set to point to a buffer
13674
** containing the text in utf-8 encoding, (*pn) is set to the size in bytes
13675
** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
13676
** if an error occurs, an SQLite error code is returned and the final values
13677
** of (*pz) and (*pn) are undefined.
13678
**
13679
** xPhraseCount:
13680
** Returns the number of phrases in the current query expression.
13681
**
13682
** xPhraseSize:
13683
** If parameter iCol is less than zero, or greater than or equal to the
13684
** number of phrases in the current query, as returned by xPhraseCount,
13685
** 0 is returned. Otherwise, this function returns the number of tokens in
13686
** phrase iPhrase of the query. Phrases are numbered starting from zero.
13687
**
13688
** xInstCount:
13689
** Set *pnInst to the total number of occurrences of all phrases within
13690
** the query within the current row. Return SQLITE_OK if successful, or
13691
** an error code (i.e. SQLITE_NOMEM) if an error occurs.
13692
**
13693
** This API can be quite slow if used with an FTS5 table created with the
13694
** "detail=none" or "detail=column" option. If the FTS5 table is created
13695
** with either "detail=none" or "detail=column" and "content=" option
13696
** (i.e. if it is a contentless table), then this API always returns 0.
13697
**
13698
** xInst:
13699
** Query for the details of phrase match iIdx within the current row.
13700
** Phrase matches are numbered starting from zero, so the iIdx argument
13701
** should be greater than or equal to zero and smaller than the value
13702
** output by xInstCount(). If iIdx is less than zero or greater than
13703
** or equal to the value returned by xInstCount(), SQLITE_RANGE is returned.
13704
**
13705
** Otherwise, output parameter *piPhrase is set to the phrase number, *piCol
13706
** to the column in which it occurs and *piOff the token offset of the
13707
** first token of the phrase. SQLITE_OK is returned if successful, or an
13708
** error code (i.e. SQLITE_NOMEM) if an error occurs.
13709
**
13710
** This API can be quite slow if used with an FTS5 table created with the
13711
** "detail=none" or "detail=column" option.
13712
**
13713
** xRowid:
13714
** Returns the rowid of the current row.
13715
**
13716
** xTokenize:
13717
** Tokenize text using the tokenizer belonging to the FTS5 table.
13718
**
13719
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
13720
** This API function is used to query the FTS table for phrase iPhrase
13721
** of the current query. Specifically, a query equivalent to:
13722
**
13723
** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
13724
**
13725
** with $p set to a phrase equivalent to the phrase iPhrase of the
13726
** current query is executed. Any column filter that applies to
13727
** phrase iPhrase of the current query is included in $p. For each
13728
** row visited, the callback function passed as the fourth argument
13729
** is invoked. The context and API objects passed to the callback
13730
** function may be used to access the properties of each matched row.
13731
** Invoking Api.xUserData() returns a copy of the pointer passed as
13732
** the third argument to pUserData.
13733
**
13734
** If parameter iPhrase is less than zero, or greater than or equal to
13735
** the number of phrases in the query, as returned by xPhraseCount(),
13736
** this function returns SQLITE_RANGE.
13737
**
13738
** If the callback function returns any value other than SQLITE_OK, the
13739
** query is abandoned and the xQueryPhrase function returns immediately.
13740
** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
13741
** Otherwise, the error code is propagated upwards.
13742
**
13743
** If the query runs to completion without incident, SQLITE_OK is returned.
13744
** Or, if some error occurs before the query completes or is aborted by
13745
** the callback, an SQLite error code is returned.
13746
**
13747
**
13748
** xSetAuxdata(pFts5, pAux, xDelete)
13749
**
13750
** Save the pointer passed as the second argument as the extension function's
13751
** "auxiliary data". The pointer may then be retrieved by the current or any
13752
** future invocation of the same fts5 extension function made as part of
13753
** the same MATCH query using the xGetAuxdata() API.
13754
**
13755
** Each extension function is allocated a single auxiliary data slot for
13756
** each FTS query (MATCH expression). If the extension function is invoked
13757
** more than once for a single FTS query, then all invocations share a
13758
** single auxiliary data context.
13759
**
13760
** If there is already an auxiliary data pointer when this function is
13761
** invoked, then it is replaced by the new pointer. If an xDelete callback
13762
** was specified along with the original pointer, it is invoked at this
13763
** point.
13764
**
13765
** The xDelete callback, if one is specified, is also invoked on the
13766
** auxiliary data pointer after the FTS5 query has finished.
13767
**
13768
** If an error (e.g. an OOM condition) occurs within this function,
13769
** the auxiliary data is set to NULL and an error code returned. If the
13770
** xDelete parameter was not NULL, it is invoked on the auxiliary data
13771
** pointer before returning.
13772
**
13773
**
13774
** xGetAuxdata(pFts5, bClear)
13775
**
13776
** Returns the current auxiliary data pointer for the fts5 extension
13777
** function. See the xSetAuxdata() method for details.
13778
**
13779
** If the bClear argument is non-zero, then the auxiliary data is cleared
13780
** (set to NULL) before this function returns. In this case the xDelete,
13781
** if any, is not invoked.
13782
**
13783
**
13784
** xRowCount(pFts5, pnRow)
13785
**
13786
** This function is used to retrieve the total number of rows in the table.
13787
** In other words, the same value that would be returned by:
13788
**
13789
** SELECT count(*) FROM ftstable;
13790
**
13791
** xPhraseFirst()
13792
** This function is used, along with type Fts5PhraseIter and the xPhraseNext
13793
** method, to iterate through all instances of a single query phrase within
13794
** the current row. This is the same information as is accessible via the
13795
** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
13796
** to use, this API may be faster under some circumstances. To iterate
13797
** through instances of phrase iPhrase, use the following code:
13798
**
13799
** Fts5PhraseIter iter;
13800
** int iCol, iOff;
13801
** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
13802
** iCol>=0;
13803
** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
13804
** ){
13805
** // An instance of phrase iPhrase at offset iOff of column iCol
13806
** }
13807
**
13808
** The Fts5PhraseIter structure is defined above. Applications should not
13809
** modify this structure directly - it should only be used as shown above
13810
** with the xPhraseFirst() and xPhraseNext() API methods (and by
13811
** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
13812
**
13813
** This API can be quite slow if used with an FTS5 table created with the
13814
** "detail=none" or "detail=column" option. If the FTS5 table is created
13815
** with either "detail=none" or "detail=column" and "content=" option
13816
** (i.e. if it is a contentless table), then this API always iterates
13817
** through an empty set (all calls to xPhraseFirst() set iCol to -1).
13818
**
13819
** In all cases, matches are visited in (column ASC, offset ASC) order.
13820
** i.e. all those in column 0, sorted by offset, followed by those in
13821
** column 1, etc.
13822
**
13823
** xPhraseNext()
13824
** See xPhraseFirst above.
13825
**
13826
** xPhraseFirstColumn()
13827
** This function and xPhraseNextColumn() are similar to the xPhraseFirst()
13828
** and xPhraseNext() APIs described above. The difference is that instead
13829
** of iterating through all instances of a phrase in the current row, these
13830
** APIs are used to iterate through the set of columns in the current row
13831
** that contain one or more instances of a specified phrase. For example:
13832
**
13833
** Fts5PhraseIter iter;
13834
** int iCol;
13835
** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
13836
** iCol>=0;
13837
** pApi->xPhraseNextColumn(pFts, &iter, &iCol)
13838
** ){
13839
** // Column iCol contains at least one instance of phrase iPhrase
13840
** }
13841
**
13842
** This API can be quite slow if used with an FTS5 table created with the
13843
** "detail=none" option. If the FTS5 table is created with either
13844
** "detail=none" "content=" option (i.e. if it is a contentless table),
13845
** then this API always iterates through an empty set (all calls to
13846
** xPhraseFirstColumn() set iCol to -1).
13847
**
13848
** The information accessed using this API and its companion
13849
** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
13850
** (or xInst/xInstCount). The chief advantage of this API is that it is
13851
** significantly more efficient than those alternatives when used with
13852
** "detail=column" tables.
13853
**
13854
** xPhraseNextColumn()
13855
** See xPhraseFirstColumn above.
13856
**
13857
** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken)
13858
** This is used to access token iToken of phrase iPhrase of the current
13859
** query. Before returning, output parameter *ppToken is set to point
13860
** to a buffer containing the requested token, and *pnToken to the
13861
** size of this buffer in bytes.
13862
**
13863
** If iPhrase or iToken are less than zero, or if iPhrase is greater than
13864
** or equal to the number of phrases in the query as reported by
13865
** xPhraseCount(), or if iToken is equal to or greater than the number of
13866
** tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken
13867
are both zeroed.
13868
**
13869
** The output text is not a copy of the query text that specified the
13870
** token. It is the output of the tokenizer module. For tokendata=1
13871
** tables, this includes any embedded 0x00 and trailing data.
13872
**
13873
** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken)
13874
** This is used to access token iToken of phrase hit iIdx within the
13875
** current row. If iIdx is less than zero or greater than or equal to the
13876
** value returned by xInstCount(), SQLITE_RANGE is returned. Otherwise,
13877
** output variable (*ppToken) is set to point to a buffer containing the
13878
** matching document token, and (*pnToken) to the size of that buffer in
13879
** bytes.
13880
**
13881
** The output text is not a copy of the document text that was tokenized.
13882
** It is the output of the tokenizer module. For tokendata=1 tables, this
13883
** includes any embedded 0x00 and trailing data.
13884
**
13885
** This API may be slow in some cases if the token identified by parameters
13886
** iIdx and iToken matched a prefix token in the query. In most cases, the
13887
** first call to this API for each prefix token in the query is forced
13888
** to scan the portion of the full-text index that matches the prefix
13889
** token to collect the extra data required by this API. If the prefix
13890
** token matches a large number of token instances in the document set,
13891
** this may be a performance problem.
13892
**
13893
** If the user knows in advance that a query may use this API for a
13894
** prefix token, FTS5 may be configured to collect all required data as part
13895
** of the initial querying of the full-text index, avoiding the second scan
13896
** entirely. This also causes prefix queries that do not use this API to
13897
** run more slowly and use more memory. FTS5 may be configured in this way
13898
** either on a per-table basis using the [FTS5 insttoken | 'insttoken']
13899
** option, or on a per-query basis using the
13900
** [fts5_insttoken | fts5_insttoken()] user function.
13901
**
13902
** This API can be quite slow if used with an FTS5 table created with the
13903
** "detail=none" or "detail=column" option.
13904
**
13905
** xColumnLocale(pFts5, iIdx, pzLocale, pnLocale)
13906
** If parameter iCol is less than zero, or greater than or equal to the
13907
** number of columns in the table, SQLITE_RANGE is returned.
13908
**
13909
** Otherwise, this function attempts to retrieve the locale associated
13910
** with column iCol of the current row. Usually, there is no associated
13911
** locale, and output parameters (*pzLocale) and (*pnLocale) are set
13912
** to NULL and 0, respectively. However, if the fts5_locale() function
13913
** was used to associate a locale with the value when it was inserted
13914
** into the fts5 table, then (*pzLocale) is set to point to a nul-terminated
13915
** buffer containing the name of the locale in utf-8 encoding. (*pnLocale)
13916
** is set to the size in bytes of the buffer, not including the
13917
** nul-terminator.
13918
**
13919
** If successful, SQLITE_OK is returned. Or, if an error occurs, an
13920
** SQLite error code is returned. The final value of the output parameters
13921
** is undefined in this case.
13922
**
13923
** xTokenize_v2:
13924
** Tokenize text using the tokenizer belonging to the FTS5 table. This
13925
** API is the same as the xTokenize() API, except that it allows a tokenizer
13926
** locale to be specified.
13927
*/
13928
struct Fts5ExtensionApi {
13929
int iVersion; /* Currently always set to 4 */
13930
13931
void *(*xUserData)(Fts5Context*);
13932
13933
int (*xColumnCount)(Fts5Context*);
13934
int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
13935
int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
13936
13937
int (*xTokenize)(Fts5Context*,
13938
const char *pText, int nText, /* Text to tokenize */
13939
void *pCtx, /* Context passed to xToken() */
13940
int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
13941
);
13942
13943
int (*xPhraseCount)(Fts5Context*);
13944
int (*xPhraseSize)(Fts5Context*, int iPhrase);
13945
13946
int (*xInstCount)(Fts5Context*, int *pnInst);
13947
int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
13948
13949
sqlite3_int64 (*xRowid)(Fts5Context*);
13950
int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
13951
int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
13952
13953
int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
13954
int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
13955
);
13956
int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
13957
void *(*xGetAuxdata)(Fts5Context*, int bClear);
13958
13959
int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
13960
void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
13961
13962
int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
13963
void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
13964
13965
/* Below this point are iVersion>=3 only */
13966
int (*xQueryToken)(Fts5Context*,
13967
int iPhrase, int iToken,
13968
const char **ppToken, int *pnToken
13969
);
13970
int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*);
13971
13972
/* Below this point are iVersion>=4 only */
13973
int (*xColumnLocale)(Fts5Context*, int iCol, const char **pz, int *pn);
13974
int (*xTokenize_v2)(Fts5Context*,
13975
const char *pText, int nText, /* Text to tokenize */
13976
const char *pLocale, int nLocale, /* Locale to pass to tokenizer */
13977
void *pCtx, /* Context passed to xToken() */
13978
int (*xToken)(void*, int, const char*, int, int, int) /* Callback */
13979
);
13980
};
13981
13982
/*
13983
** CUSTOM AUXILIARY FUNCTIONS
13984
*************************************************************************/
13985
13986
/*************************************************************************
13987
** CUSTOM TOKENIZERS
13988
**
13989
** Applications may also register custom tokenizer types. A tokenizer
13990
** is registered by providing fts5 with a populated instance of the
13991
** following structure. All structure methods must be defined, setting
13992
** any member of the fts5_tokenizer struct to NULL leads to undefined
13993
** behaviour. The structure methods are expected to function as follows:
13994
**
13995
** xCreate:
13996
** This function is used to allocate and initialize a tokenizer instance.
13997
** A tokenizer instance is required to actually tokenize text.
13998
**
13999
** The first argument passed to this function is a copy of the (void*)
14000
** pointer provided by the application when the fts5_tokenizer_v2 object
14001
** was registered with FTS5 (the third argument to xCreateTokenizer()).
14002
** The second and third arguments are an array of nul-terminated strings
14003
** containing the tokenizer arguments, if any, specified following the
14004
** tokenizer name as part of the CREATE VIRTUAL TABLE statement used
14005
** to create the FTS5 table.
14006
**
14007
** The final argument is an output variable. If successful, (*ppOut)
14008
** should be set to point to the new tokenizer handle and SQLITE_OK
14009
** returned. If an error occurs, some value other than SQLITE_OK should
14010
** be returned. In this case, fts5 assumes that the final value of *ppOut
14011
** is undefined.
14012
**
14013
** xDelete:
14014
** This function is invoked to delete a tokenizer handle previously
14015
** allocated using xCreate(). Fts5 guarantees that this function will
14016
** be invoked exactly once for each successful call to xCreate().
14017
**
14018
** xTokenize:
14019
** This function is expected to tokenize the nText byte string indicated
14020
** by argument pText. pText may or may not be nul-terminated. The first
14021
** argument passed to this function is a pointer to an Fts5Tokenizer object
14022
** returned by an earlier call to xCreate().
14023
**
14024
** The third argument indicates the reason that FTS5 is requesting
14025
** tokenization of the supplied text. This is always one of the following
14026
** four values:
14027
**
14028
** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
14029
** or removed from the FTS table. The tokenizer is being invoked to
14030
** determine the set of tokens to add to (or delete from) the
14031
** FTS index.
14032
**
14033
** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
14034
** against the FTS index. The tokenizer is being called to tokenize
14035
** a bareword or quoted string specified as part of the query.
14036
**
14037
** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
14038
** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
14039
** followed by a "*" character, indicating that the last token
14040
** returned by the tokenizer will be treated as a token prefix.
14041
**
14042
** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
14043
** satisfy an fts5_api.xTokenize() request made by an auxiliary
14044
** function. Or an fts5_api.xColumnSize() request made by the same
14045
** on a columnsize=0 database.
14046
** </ul>
14047
**
14048
** The sixth and seventh arguments passed to xTokenize() - pLocale and
14049
** nLocale - are a pointer to a buffer containing the locale to use for
14050
** tokenization (e.g. "en_US") and its size in bytes, respectively. The
14051
** pLocale buffer is not nul-terminated. pLocale may be passed NULL (in
14052
** which case nLocale is always 0) to indicate that the tokenizer should
14053
** use its default locale.
14054
**
14055
** For each token in the input string, the supplied callback xToken() must
14056
** be invoked. The first argument to it should be a copy of the pointer
14057
** passed as the second argument to xTokenize(). The third and fourth
14058
** arguments are a pointer to a buffer containing the token text, and the
14059
** size of the token in bytes. The 4th and 5th arguments are the byte offsets
14060
** of the first byte of and first byte immediately following the text from
14061
** which the token is derived within the input.
14062
**
14063
** The second argument passed to the xToken() callback ("tflags") should
14064
** normally be set to 0. The exception is if the tokenizer supports
14065
** synonyms. In this case see the discussion below for details.
14066
**
14067
** FTS5 assumes the xToken() callback is invoked for each token in the
14068
** order that they occur within the input text.
14069
**
14070
** If an xToken() callback returns any value other than SQLITE_OK, then
14071
** the tokenization should be abandoned and the xTokenize() method should
14072
** immediately return a copy of the xToken() return value. Or, if the
14073
** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
14074
** if an error occurs with the xTokenize() implementation itself, it
14075
** may abandon the tokenization and return any error code other than
14076
** SQLITE_OK or SQLITE_DONE.
14077
**
14078
** If the tokenizer is registered using an fts5_tokenizer_v2 object,
14079
** then the xTokenize() method has two additional arguments - pLocale
14080
** and nLocale. These specify the locale that the tokenizer should use
14081
** for the current request. If pLocale and nLocale are both 0, then the
14082
** tokenizer should use its default locale. Otherwise, pLocale points to
14083
** an nLocale byte buffer containing the name of the locale to use as utf-8
14084
** text. pLocale is not nul-terminated.
14085
**
14086
** FTS5_TOKENIZER
14087
**
14088
** There is also an fts5_tokenizer object. This is an older, deprecated,
14089
** version of fts5_tokenizer_v2. It is similar except that:
14090
**
14091
** <ul>
14092
** <li> There is no "iVersion" field, and
14093
** <li> The xTokenize() method does not take a locale argument.
14094
** </ul>
14095
**
14096
** Legacy fts5_tokenizer tokenizers must be registered using the
14097
** legacy xCreateTokenizer() function, instead of xCreateTokenizer_v2().
14098
**
14099
** Tokenizer implementations registered using either API may be retrieved
14100
** using both xFindTokenizer() and xFindTokenizer_v2().
14101
**
14102
** SYNONYM SUPPORT
14103
**
14104
** Custom tokenizers may also support synonyms. Consider a case in which a
14105
** user wishes to query for a phrase such as "first place". Using the
14106
** built-in tokenizers, the FTS5 query 'first + place' will match instances
14107
** of "first place" within the document set, but not alternative forms
14108
** such as "1st place". In some applications, it would be better to match
14109
** all instances of "first place" or "1st place" regardless of which form
14110
** the user specified in the MATCH query text.
14111
**
14112
** There are several ways to approach this in FTS5:
14113
**
14114
** <ol><li> By mapping all synonyms to a single token. In this case, using
14115
** the above example, this means that the tokenizer returns the
14116
** same token for inputs "first" and "1st". Say that token is in
14117
** fact "first", so that when the user inserts the document "I won
14118
** 1st place" entries are added to the index for tokens "i", "won",
14119
** "first" and "place". If the user then queries for '1st + place',
14120
** the tokenizer substitutes "first" for "1st" and the query works
14121
** as expected.
14122
**
14123
** <li> By querying the index for all synonyms of each query term
14124
** separately. In this case, when tokenizing query text, the
14125
** tokenizer may provide multiple synonyms for a single term
14126
** within the document. FTS5 then queries the index for each
14127
** synonym individually. For example, faced with the query:
14128
**
14129
** <codeblock>
14130
** ... MATCH 'first place'</codeblock>
14131
**
14132
** the tokenizer offers both "1st" and "first" as synonyms for the
14133
** first token in the MATCH query and FTS5 effectively runs a query
14134
** similar to:
14135
**
14136
** <codeblock>
14137
** ... MATCH '(first OR 1st) place'</codeblock>
14138
**
14139
** except that, for the purposes of auxiliary functions, the query
14140
** still appears to contain just two phrases - "(first OR 1st)"
14141
** being treated as a single phrase.
14142
**
14143
** <li> By adding multiple synonyms for a single term to the FTS index.
14144
** Using this method, when tokenizing document text, the tokenizer
14145
** provides multiple synonyms for each token. So that when a
14146
** document such as "I won first place" is tokenized, entries are
14147
** added to the FTS index for "i", "won", "first", "1st" and
14148
** "place".
14149
**
14150
** This way, even if the tokenizer does not provide synonyms
14151
** when tokenizing query text (it should not - to do so would be
14152
** inefficient), it doesn't matter if the user queries for
14153
** 'first + place' or '1st + place', as there are entries in the
14154
** FTS index corresponding to both forms of the first token.
14155
** </ol>
14156
**
14157
** Whether it is parsing document or query text, any call to xToken that
14158
** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
14159
** is considered to supply a synonym for the previous token. For example,
14160
** when parsing the document "I won first place", a tokenizer that supports
14161
** synonyms would call xToken() 5 times, as follows:
14162
**
14163
** <codeblock>
14164
** xToken(pCtx, 0, "i", 1, 0, 1);
14165
** xToken(pCtx, 0, "won", 3, 2, 5);
14166
** xToken(pCtx, 0, "first", 5, 6, 11);
14167
** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);
14168
** xToken(pCtx, 0, "place", 5, 12, 17);
14169
**</codeblock>
14170
**
14171
** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
14172
** xToken() is called. Multiple synonyms may be specified for a single token
14173
** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
14174
** There is no limit to the number of synonyms that may be provided for a
14175
** single token.
14176
**
14177
** In many cases, method (1) above is the best approach. It does not add
14178
** extra data to the FTS index or require FTS5 to query for multiple terms,
14179
** so it is efficient in terms of disk space and query speed. However, it
14180
** does not support prefix queries very well. If, as suggested above, the
14181
** token "first" is substituted for "1st" by the tokenizer, then the query:
14182
**
14183
** <codeblock>
14184
** ... MATCH '1s*'</codeblock>
14185
**
14186
** will not match documents that contain the token "1st" (as the tokenizer
14187
** will probably not map "1s" to any prefix of "first").
14188
**
14189
** For full prefix support, method (3) may be preferred. In this case,
14190
** because the index contains entries for both "first" and "1st", prefix
14191
** queries such as 'fi*' or '1s*' will match correctly. However, because
14192
** extra entries are added to the FTS index, this method uses more space
14193
** within the database.
14194
**
14195
** Method (2) offers a midpoint between (1) and (3). Using this method,
14196
** a query such as '1s*' will match documents that contain the literal
14197
** token "1st", but not "first" (assuming the tokenizer is not able to
14198
** provide synonyms for prefixes). However, a non-prefix query like '1st'
14199
** will match against "1st" and "first". This method does not require
14200
** extra disk space, as no extra entries are added to the FTS index.
14201
** On the other hand, it may require more CPU cycles to run MATCH queries,
14202
** as separate queries of the FTS index are required for each synonym.
14203
**
14204
** When using methods (2) or (3), it is important that the tokenizer only
14205
** provide synonyms when tokenizing document text (method (3)) or query
14206
** text (method (2)), not both. Doing so will not cause any errors, but is
14207
** inefficient.
14208
*/
14209
typedef struct Fts5Tokenizer Fts5Tokenizer;
14210
typedef struct fts5_tokenizer_v2 fts5_tokenizer_v2;
14211
struct fts5_tokenizer_v2 {
14212
int iVersion; /* Currently always 2 */
14213
14214
int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
14215
void (*xDelete)(Fts5Tokenizer*);
14216
int (*xTokenize)(Fts5Tokenizer*,
14217
void *pCtx,
14218
int flags, /* Mask of FTS5_TOKENIZE_* flags */
14219
const char *pText, int nText,
14220
const char *pLocale, int nLocale,
14221
int (*xToken)(
14222
void *pCtx, /* Copy of 2nd argument to xTokenize() */
14223
int tflags, /* Mask of FTS5_TOKEN_* flags */
14224
const char *pToken, /* Pointer to buffer containing token */
14225
int nToken, /* Size of token in bytes */
14226
int iStart, /* Byte offset of token within input text */
14227
int iEnd /* Byte offset of end of token within input text */
14228
)
14229
);
14230
};
14231
14232
/*
14233
** New code should use the fts5_tokenizer_v2 type to define tokenizer
14234
** implementations. The following type is included for legacy applications
14235
** that still use it.
14236
*/
14237
typedef struct fts5_tokenizer fts5_tokenizer;
14238
struct fts5_tokenizer {
14239
int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
14240
void (*xDelete)(Fts5Tokenizer*);
14241
int (*xTokenize)(Fts5Tokenizer*,
14242
void *pCtx,
14243
int flags, /* Mask of FTS5_TOKENIZE_* flags */
14244
const char *pText, int nText,
14245
int (*xToken)(
14246
void *pCtx, /* Copy of 2nd argument to xTokenize() */
14247
int tflags, /* Mask of FTS5_TOKEN_* flags */
14248
const char *pToken, /* Pointer to buffer containing token */
14249
int nToken, /* Size of token in bytes */
14250
int iStart, /* Byte offset of token within input text */
14251
int iEnd /* Byte offset of end of token within input text */
14252
)
14253
);
14254
};
14255
14256
14257
/* Flags that may be passed as the third argument to xTokenize() */
14258
#define FTS5_TOKENIZE_QUERY 0x0001
14259
#define FTS5_TOKENIZE_PREFIX 0x0002
14260
#define FTS5_TOKENIZE_DOCUMENT 0x0004
14261
#define FTS5_TOKENIZE_AUX 0x0008
14262
14263
/* Flags that may be passed by the tokenizer implementation back to FTS5
14264
** as the third argument to the supplied xToken callback. */
14265
#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */
14266
14267
/*
14268
** END OF CUSTOM TOKENIZERS
14269
*************************************************************************/
14270
14271
/*************************************************************************
14272
** FTS5 EXTENSION REGISTRATION API
14273
*/
14274
typedef struct fts5_api fts5_api;
14275
struct fts5_api {
14276
int iVersion; /* Currently always set to 3 */
14277
14278
/* Create a new tokenizer */
14279
int (*xCreateTokenizer)(
14280
fts5_api *pApi,
14281
const char *zName,
14282
void *pUserData,
14283
fts5_tokenizer *pTokenizer,
14284
void (*xDestroy)(void*)
14285
);
14286
14287
/* Find an existing tokenizer */
14288
int (*xFindTokenizer)(
14289
fts5_api *pApi,
14290
const char *zName,
14291
void **ppUserData,
14292
fts5_tokenizer *pTokenizer
14293
);
14294
14295
/* Create a new auxiliary function */
14296
int (*xCreateFunction)(
14297
fts5_api *pApi,
14298
const char *zName,
14299
void *pUserData,
14300
fts5_extension_function xFunction,
14301
void (*xDestroy)(void*)
14302
);
14303
14304
/* APIs below this point are only available if iVersion>=3 */
14305
14306
/* Create a new tokenizer */
14307
int (*xCreateTokenizer_v2)(
14308
fts5_api *pApi,
14309
const char *zName,
14310
void *pUserData,
14311
fts5_tokenizer_v2 *pTokenizer,
14312
void (*xDestroy)(void*)
14313
);
14314
14315
/* Find an existing tokenizer */
14316
int (*xFindTokenizer_v2)(
14317
fts5_api *pApi,
14318
const char *zName,
14319
void **ppUserData,
14320
fts5_tokenizer_v2 **ppTokenizer
14321
);
14322
};
14323
14324
/*
14325
** END OF REGISTRATION API
14326
*************************************************************************/
14327
14328
#ifdef __cplusplus
14329
} /* end of the 'extern "C"' block */
14330
#endif
14331
14332
#endif /* _FTS5_H */
14333
14334
/******** End of fts5.h *********/
14335
#endif /* SQLITE3_H */
14336

Keyboard Shortcuts

Open search /
Next entry (timeline) j
Previous entry (timeline) k
Open focused entry Enter
Show this help ?
Toggle theme Top nav button