/ Check-in [08276df3]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Updates to API documentation contained in comments of sqlite.h.in. (CVS 4804)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 08276df3fdd63f210d502c414390f1efd8ebbbb7
User & Date: drh 2008-02-21 20:17:07
Context
2008-02-21
20:40
Accept "Z" as the zulu timezone at the end of date strings. (CVS 4805) check-in: 4c9a7b42 user: drh tags: trunk
20:17
Updates to API documentation contained in comments of sqlite.h.in. (CVS 4804) check-in: 08276df3 user: drh tags: trunk
02:09
Test coverage and documentation improvements. (CVS 4803) check-in: e0baceac user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/sqlite.h.in.

26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
..
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
...
330
331
332
333
334
335
336
337

338
339
340
341
342
343
344
...
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
....
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
....
4656
4657
4658
4659
4660
4661
4662



4663
4664
4665
4666
4667
4668
4669
....
4692
4693
4694
4695
4696
4697
4698



4699
4700
4701
4702
4703
4704
4705
....
4772
4773
4774
4775
4776
4777
4778


4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791


4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804



4805
4806
4807
4808
4809
4810
4811
....
4821
4822
4823
4824
4825
4826
4827




4828
4829
4830
4831
4832
4833
4834
4835
....
4836
4837
4838
4839
4840
4841
4842


4843
4844
4845
4846
4847
4848
4849


4850
4851
4852
4853
4854
4855
4856
....
4875
4876
4877
4878
4879
4880
4881
4882
4883

4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914




















4915
4916
4917
4918
4919
4920
4921
....
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942


















4943
4944
4945
4946
4947
4948
4949
4950






4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967



























4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990































4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022



























5023
5024
5025
5026
5027
5028
5029
** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.286 2008/02/21 02:09:45 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.
................................................................................
**          with which the header file is associated.
**
** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer
**          with the value  (X*1000000 + Y*1000 + Z) where X, Y, and
**          Z are the major version, minor version, and release number.
*/
#define SQLITE_VERSION         "--VERS--"
#define SQLITE_VERSION_NUMBER --VERSION-NUMBER--

/*
** CAPI3REF: Run-Time Library Version Numbers {F10020}
** KEYWORDS: sqlite3_version
**
** These features provide the same information as the [SQLITE_VERSION]
** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
................................................................................
**          allocated using the equivalent of [sqlite3_mprintf()] and
**          *errmsg is made to point to that message.
**
** {F12134} The [sqlite3_exec()] routine does not change the value of
**          *errmsg if errmsg is NULL or if there are no errors.
**
** {F12137} The [sqlite3_exec()] function sets the error code and message
**          accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].

**
** LIMITATIONS:
**
** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open
**          [database connection].
**
** {U12142} The database connection must not be closed while
................................................................................
** versions of SQLite.  Additional fields may be appended to this
** object when the iVersion value is increased.
**
** The szOsFile field is the size of the subclassed [sqlite3_file]
** structure used by this VFS.  mxPathname is the maximum length of
** a pathname in this VFS.
**
** Registered vfs modules are kept on a linked list formed by
** the pNext pointer.  The [sqlite3_vfs_register()]
** and [sqlite3_vfs_unregister()] interfaces manage this list
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
** searches the list.
**
** The pNext field is the only fields in the sqlite3_vfs 
** structure that SQLite will ever modify.  SQLite will only access
................................................................................
** subsequent calls to other SQLite interface functions.
**
** INVARIANTS:
**
** {F12801} The [sqlite3_errcode(D)] interface returns the numeric
**          [SQLITE_OK | result code] or
**          [SQLITE_IOERR_READ | extended result code]
**          for the most recent failed interface call associated
**          with [sqlite3] handle D.
**
** {U12802} If a prior API call failed but the most recent API call
**          succeeded, the return value from [sqlite3_errcode()],
**          [sqlite3_errmsg()], and [sqlite3_errmsg16()] are undefined.
**
** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
**          interfaces return English-language text that describes
**          the error in the mostly recently failed interface call,
**          encoded as either UTF8 or UTF16 respectively.
**
** {U12804} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
**          are only valid until the next SQLite interface call.
**
** {F12807} Calls to [sqlite3_errcode()], [sqlite3_errmsg()], and
**          [sqlite3_errmsg16()] themselves do not affect the
**          results of future invocations of these routines.
**
** {F12808} Calls to API routines that do not return an error code
**          (example: [sqlite3_data_count()]) do not
**          change the error code or message returned by
**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
**
** {F12809} Interfaces that are not associated with a specific
................................................................................
*/
typedef struct sqlite3_vtab sqlite3_vtab;
typedef struct sqlite3_index_info sqlite3_index_info;
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
typedef struct sqlite3_module sqlite3_module;

/*



** A module is a class of virtual tables.  Each module is defined
** by an instance of the following structure.  This structure consists
** mostly of methods for the module.
*/
struct sqlite3_module {
  int iVersion;
  int (*xCreate)(sqlite3*, void *pAux,
................................................................................
                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                       void **ppArg);

  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
};

/*



** The sqlite3_index_info structure and its substructures is used to
** pass information into and receive the reply from the xBestIndex
** method of an sqlite3_module.  The fields under **Inputs** are the
** inputs to xBestIndex and are read-only.  xBestIndex inserts its
** results into the **Outputs** fields.
**
** The aConstraint[] array records WHERE clause constraints of the
................................................................................
#define SQLITE_INDEX_CONSTRAINT_GT    4
#define SQLITE_INDEX_CONSTRAINT_LE    8
#define SQLITE_INDEX_CONSTRAINT_LT    16
#define SQLITE_INDEX_CONSTRAINT_GE    32
#define SQLITE_INDEX_CONSTRAINT_MATCH 64

/*


** This routine is used to register a new module name with an SQLite
** connection.  Module names must be registered before creating new
** virtual tables on the module, or before using preexisting virtual
** tables of the module.
*/
int sqlite3_create_module(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *,    /* Methods for the module */
  void *                     /* Client data for xCreate/xConnect */
);

/*


** This routine is identical to the sqlite3_create_module() method above,
** except that it allows a destructor function to be specified. It is
** even more experimental than the rest of the virtual tables API.
*/
int sqlite3_create_module_v2(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *,    /* Methods for the module */
  void *,                    /* Client data for xCreate/xConnect */
  void(*xDestroy)(void*)     /* Module destructor function */
);

/*



** Every module implementation uses a subclass of the following structure
** to describe a particular instance of the module.  Each subclass will
** be tailored to the specific needs of the module implementation.   The
** purpose of this superclass is to define certain fields that are common
** to all module implementations.
**
** Virtual tables methods can set an error message by assigning a
................................................................................
struct sqlite3_vtab {
  const sqlite3_module *pModule;  /* The module for this virtual table */
  int nRef;                       /* Used internally */
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
  /* Virtual table implementations will typically add additional fields */
};





/* Every module implementation uses a subclass of the following structure
** to describe cursors that point into the virtual table and are used
** to loop through the virtual table.  Cursors are created using the
** xOpen method of the module.  Each module implementation will define
** the content of a cursor structure to suit its own needs.
**
** This superclass exists in order to define fields of the cursor that
** are common to all implementations.
................................................................................
*/
struct sqlite3_vtab_cursor {
  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
  /* Virtual table implementations will typically add additional fields */
};

/*


** The xCreate and xConnect methods of a module use the following API
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);

/*


** Virtual tables can provide alternative implementations of functions
** using the xFindFunction method.  But global versions of those functions
** must exist in order to be overloaded.
**
** This API makes sure a global version of a function with a particular
** name and number of parameters exists.  If no such function exists
** before this API is called, a new function is created.  The implementation
................................................................................
**
****** EXPERIMENTAL - subject to change without notice **************
*/

/*
** CAPI3REF: A Handle To An Open BLOB {F17800}
**
** An instance of the following opaque structure is used to 
** represent an blob-handle.  A blob-handle is created by

** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
** can be used to read or write small subsections of the blob.
** The [sqlite3_blob_bytes()] interface returns the size of the
** blob in bytes.
*/
typedef struct sqlite3_blob sqlite3_blob;

/*
** CAPI3REF: Open A BLOB For Incremental I/O {F17810}
**
** {F17811} This interfaces opens a handle to the blob located
** in row iRow,, column zColumn, table zTable in database zDb;
** in other words,  the same blob that would be selected by:
**
** <pre>
**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
** </pre> {END}
**
** {F17812} If the flags parameter is non-zero, the blob is opened for 
** read and write access. If it is zero, the blob is opened for read 
** access. {END}
**
** {F17813} On success, [SQLITE_OK] is returned and the new 
** [sqlite3_blob | blob handle] is written to *ppBlob. 
** {F17814} Otherwise an error code is returned and 
** any value written to *ppBlob should not be used by the caller.
** {F17815} This function sets the database-handle error code and message
** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
** <todo>We should go through and mark all interfaces that behave this
** way with a similar statement</todo>




















*/
int sqlite3_blob_open(
  sqlite3*,
  const char *zDb,
  const char *zTable,
  const char *zColumn,
  sqlite3_int64 iRow,
................................................................................
);

/*
** CAPI3REF:  Close A BLOB Handle {F17830}
**
** Close an open [sqlite3_blob | blob handle].
**
** {F17831} Closing a BLOB shall cause the current transaction to commit
** if there are no other BLOBs, no pending prepared statements, and the
** database connection is in autocommit mode.
** {F17832} If any writes were made to the BLOB, they might be held in cache
** until the close operation if they will fit. {END}
** Closing the BLOB often forces the changes
** out to disk and so if any I/O errors occur, they will likely occur
** at the time when the BLOB is closed.  {F17833} Any errors that occur during
** closing are reported as a non-zero return value.
**
** {F17839} The BLOB is closed unconditionally.  Even if this routine returns
** an error code, the BLOB is still closed.


















*/
int sqlite3_blob_close(sqlite3_blob *);

/*
** CAPI3REF:  Return The Size Of An Open BLOB {F17805}
**
** {F16806} Return the size in bytes of the blob accessible via the open 
** [sqlite3_blob | blob-handle] passed as an argument.






*/
int sqlite3_blob_bytes(sqlite3_blob *);

/*
** CAPI3REF:  Read Data From A BLOB Incrementally {F17850}
**
** This function is used to read data from an open 
** [sqlite3_blob | blob-handle] into a caller supplied buffer.
** {F17851} n bytes of data are copied into buffer
** z from the open blob, starting at offset iOffset.
**
** {F17852} If offset iOffset is less than n bytes from the end of the blob, 
** [SQLITE_ERROR] is returned and no data is read.  {F17853} If n is
** less than zero [SQLITE_ERROR] is returned and no data is read.
**
** {F17854} On success, SQLITE_OK is returned. Otherwise, an 
** [error code] or an [extended error code] is returned.



























*/
int sqlite3_blob_read(sqlite3_blob *, void *z, int n, int iOffset);

/*
** CAPI3REF:  Write Data Into A BLOB Incrementally {F17870}
**
** This function is used to write data into an open 
** [sqlite3_blob | blob-handle] from a user supplied buffer.
** {F17871} n bytes of data are copied from the buffer
** pointed to by z into the open blob, starting at offset iOffset.
**
** {F17872} If the [sqlite3_blob | blob-handle] passed as the first argument
** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
*** was zero), this function returns [SQLITE_READONLY].
**
** {F17873} This function may only modify the contents of the blob; it is
** not possible to increase the size of a blob using this API.
** {F17874} If offset iOffset is less than n bytes from the end of the blob, 
** [SQLITE_ERROR] is returned and no data is written.  {F17875} If n is
** less than zero [SQLITE_ERROR] is returned and no data is written.
**
** {F17876} On success, SQLITE_OK is returned. Otherwise, an 
** [error code] or an [extended error code] is returned.































*/
int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);

/*
** CAPI3REF:  Virtual File System Objects {F11200}
**
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
** that SQLite uses to interact
** with the underlying operating system.  Most builds come with a
** single default VFS that is appropriate for the host computer.
** New VFSes can be registered and existing VFSes can be unregistered.
** The following interfaces are provided.
**
** {F11201} The sqlite3_vfs_find() interface returns a pointer to 
** a VFS given its name.  {F11202} Names are case sensitive.
** {F11203} Names are zero-terminated UTF-8 strings.
** {F11204} If there is no match, a NULL
** pointer is returned. {F11205} If zVfsName is NULL then the default 
** VFS is returned. {END}
**
** {F11210} New VFSes are registered with sqlite3_vfs_register().
** {F11211} Each new VFS becomes the default VFS if the makeDflt flag is set.
** {F11212} The same VFS can be registered multiple times without injury.
** {F11213} To make an existing VFS into the default VFS, register it again
** with the makeDflt flag set. {U11214} If two different VFSes with the
** same name are registered, the behavior is undefined.  {U11215} If a
** VFS is registered with a name that is NULL or an empty string,
** then the behavior is undefined.
** 
** {F11220} Unregister a VFS with the sqlite3_vfs_unregister() interface.
** {F11221} If the default VFS is unregistered, another VFS is chosen as
** the default.  The choice for the new VFS is arbitrary.



























*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
int sqlite3_vfs_unregister(sqlite3_vfs*);

/*
** CAPI3REF: Mutexes {F17000}







|







 







|







 







|
>







 







|







 







|
|
<
<
<
<






|
|
<
<
<
<







 







>
>
>







 







>
>
>







 







>
>













>
>













>
>
>







 







>
>
>
>
|







 







>
>







>
>







 







|
|
>











|







|

|

|

|

|

|
|
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







 







|


|






|

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>




|

|
|
>
>
>
>
>
>








|
|

|
|


|

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

|






|


|



|

|
|


|

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>








|




|
|
|
|
|
|

|
|
|
|
|
|



|
|

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
..
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
...
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
...
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
....
2074
2075
2076
2077
2078
2079
2080
2081
2082




2083
2084
2085
2086
2087
2088
2089
2090




2091
2092
2093
2094
2095
2096
2097
....
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
....
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
....
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
....
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
....
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
....
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
....
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.287 2008/02/21 20:17:07 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.
................................................................................
**          with which the header file is associated.
**
** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer
**          with the value  (X*1000000 + Y*1000 + Z) where X, Y, and
**          Z are the major version, minor version, and release number.
*/
#define SQLITE_VERSION         "--VERS--"
#define SQLITE_VERSION_NUMBER  --VERSION-NUMBER--

/*
** CAPI3REF: Run-Time Library Version Numbers {F10020}
** KEYWORDS: sqlite3_version
**
** These features provide the same information as the [SQLITE_VERSION]
** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated
................................................................................
**          allocated using the equivalent of [sqlite3_mprintf()] and
**          *errmsg is made to point to that message.
**
** {F12134} The [sqlite3_exec()] routine does not change the value of
**          *errmsg if errmsg is NULL or if there are no errors.
**
** {F12137} The [sqlite3_exec()] function sets the error code and message
**          accessible via [sqlite3_errcode()], [sqlite3_errmsg()], and
**          [sqlite3_errmsg16()].
**
** LIMITATIONS:
**
** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open
**          [database connection].
**
** {U12142} The database connection must not be closed while
................................................................................
** versions of SQLite.  Additional fields may be appended to this
** object when the iVersion value is increased.
**
** The szOsFile field is the size of the subclassed [sqlite3_file]
** structure used by this VFS.  mxPathname is the maximum length of
** a pathname in this VFS.
**
** Registered sqlite3_vfs objects are kept on a linked list formed by
** the pNext pointer.  The [sqlite3_vfs_register()]
** and [sqlite3_vfs_unregister()] interfaces manage this list
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
** searches the list.
**
** The pNext field is the only fields in the sqlite3_vfs 
** structure that SQLite will ever modify.  SQLite will only access
................................................................................
** subsequent calls to other SQLite interface functions.
**
** INVARIANTS:
**
** {F12801} The [sqlite3_errcode(D)] interface returns the numeric
**          [SQLITE_OK | result code] or
**          [SQLITE_IOERR_READ | extended result code]
**          for the most recently failed interface call associated
**          with [database connection] D.




**
** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)]
**          interfaces return English-language text that describes
**          the error in the mostly recently failed interface call,
**          encoded as either UTF8 or UTF16 respectively.
**
** {F12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]
**          are valid until the next SQLite interface call.




**
** {F12808} Calls to API routines that do not return an error code
**          (example: [sqlite3_data_count()]) do not
**          change the error code or message returned by
**          [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()].
**
** {F12809} Interfaces that are not associated with a specific
................................................................................
*/
typedef struct sqlite3_vtab sqlite3_vtab;
typedef struct sqlite3_index_info sqlite3_index_info;
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
typedef struct sqlite3_module sqlite3_module;

/*
** CAPI3REF: Virtual Table Object {F18000}
** KEYWORDS: sqlite3_module
**
** A module is a class of virtual tables.  Each module is defined
** by an instance of the following structure.  This structure consists
** mostly of methods for the module.
*/
struct sqlite3_module {
  int iVersion;
  int (*xCreate)(sqlite3*, void *pAux,
................................................................................
                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                       void **ppArg);

  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
};

/*
** CAPI3REF: Virtual Table Indexing Information {F18100}
** KEYWORDS: sqlite3_index_info
**
** The sqlite3_index_info structure and its substructures is used to
** pass information into and receive the reply from the xBestIndex
** method of an sqlite3_module.  The fields under **Inputs** are the
** inputs to xBestIndex and are read-only.  xBestIndex inserts its
** results into the **Outputs** fields.
**
** The aConstraint[] array records WHERE clause constraints of the
................................................................................
#define SQLITE_INDEX_CONSTRAINT_GT    4
#define SQLITE_INDEX_CONSTRAINT_LE    8
#define SQLITE_INDEX_CONSTRAINT_LT    16
#define SQLITE_INDEX_CONSTRAINT_GE    32
#define SQLITE_INDEX_CONSTRAINT_MATCH 64

/*
** CAPI3REF: Register A Virtual Table Implementation {F18200}
**
** This routine is used to register a new module name with an SQLite
** connection.  Module names must be registered before creating new
** virtual tables on the module, or before using preexisting virtual
** tables of the module.
*/
int sqlite3_create_module(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *,    /* Methods for the module */
  void *                     /* Client data for xCreate/xConnect */
);

/*
** CAPI3REF: Register A Virtual Table Implementation {F18210}
**
** This routine is identical to the sqlite3_create_module() method above,
** except that it allows a destructor function to be specified. It is
** even more experimental than the rest of the virtual tables API.
*/
int sqlite3_create_module_v2(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *,    /* Methods for the module */
  void *,                    /* Client data for xCreate/xConnect */
  void(*xDestroy)(void*)     /* Module destructor function */
);

/*
** CAPI3REF: Virtual Table Instance Object {F18010}
** KEYWORDS: sqlite3_vtab
**
** Every module implementation uses a subclass of the following structure
** to describe a particular instance of the module.  Each subclass will
** be tailored to the specific needs of the module implementation.   The
** purpose of this superclass is to define certain fields that are common
** to all module implementations.
**
** Virtual tables methods can set an error message by assigning a
................................................................................
struct sqlite3_vtab {
  const sqlite3_module *pModule;  /* The module for this virtual table */
  int nRef;                       /* Used internally */
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
  /* Virtual table implementations will typically add additional fields */
};

/*
** CAPI3REF: Virtual Table Cursor Object  {F18020}
** KEYWORDS: sqlite3_vtab_cursor
**
** Every module implementation uses a subclass of the following structure
** to describe cursors that point into the virtual table and are used
** to loop through the virtual table.  Cursors are created using the
** xOpen method of the module.  Each module implementation will define
** the content of a cursor structure to suit its own needs.
**
** This superclass exists in order to define fields of the cursor that
** are common to all implementations.
................................................................................
*/
struct sqlite3_vtab_cursor {
  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
  /* Virtual table implementations will typically add additional fields */
};

/*
** CAPI3REF: Declare The Schema Of A Virtual Table {F18280}
**
** The xCreate and xConnect methods of a module use the following API
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);

/*
** CAPI3REF: Overload A Function For A Virtual Table {F18300}
**
** Virtual tables can provide alternative implementations of functions
** using the xFindFunction method.  But global versions of those functions
** must exist in order to be overloaded.
**
** This API makes sure a global version of a function with a particular
** name and number of parameters exists.  If no such function exists
** before this API is called, a new function is created.  The implementation
................................................................................
**
****** EXPERIMENTAL - subject to change without notice **************
*/

/*
** CAPI3REF: A Handle To An Open BLOB {F17800}
**
** An instance of this object represents an open BLOB on which
** incremental I/O can be preformed.
** Objects of this type are created by
** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
** can be used to read or write small subsections of the blob.
** The [sqlite3_blob_bytes()] interface returns the size of the
** blob in bytes.
*/
typedef struct sqlite3_blob sqlite3_blob;

/*
** CAPI3REF: Open A BLOB For Incremental I/O {F17810}
**
** This interfaces opens a handle to the blob located
** in row iRow,, column zColumn, table zTable in database zDb;
** in other words,  the same blob that would be selected by:
**
** <pre>
**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
** </pre> {END}
**
** If the flags parameter is non-zero, the blob is opened for 
** read and write access. If it is zero, the blob is opened for read 
** access.
**
** On success, [SQLITE_OK] is returned and the new 
** [sqlite3_blob | blob handle] is written to *ppBlob. 
** Otherwise an error code is returned and 
** any value written to *ppBlob should not be used by the caller.
** This function sets the database-handle error code and message
** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
** 
** INVARIANTS:
**
** {F17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)]
**          interface opens an [sqlite3_blob] object P on the blob
**          in column C of table T in database B on [database connection] D.
**
** {F17814} A successful invocation of [sqlite3_blob_open(D,...)] starts
**          a new transaction on [database connection] D if that connection
**          is not already in a transaction.
**
** {F17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface opens the blob
**          for read and write access if and only if the F parameter
**          is non-zero.
**
** {F17819} The [sqlite3_blob_open()] interface returns [SQLITE_OK] on 
**          success and an appropriate [error code] on failure.
**
** {F17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)]
**          then subsequent calls to [sqlite3_errcode(D)],
**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
**          information approprate for that error.
*/
int sqlite3_blob_open(
  sqlite3*,
  const char *zDb,
  const char *zTable,
  const char *zColumn,
  sqlite3_int64 iRow,
................................................................................
);

/*
** CAPI3REF:  Close A BLOB Handle {F17830}
**
** Close an open [sqlite3_blob | blob handle].
**
** Closing a BLOB shall cause the current transaction to commit
** if there are no other BLOBs, no pending prepared statements, and the
** database connection is in autocommit mode.
** If any writes were made to the BLOB, they might be held in cache
** until the close operation if they will fit. {END}
** Closing the BLOB often forces the changes
** out to disk and so if any I/O errors occur, they will likely occur
** at the time when the BLOB is closed.  {F17833} Any errors that occur during
** closing are reported as a non-zero return value.
**
** The BLOB is closed unconditionally.  Even if this routine returns
** an error code, the BLOB is still closed.
**
** INVARIANTS:
**
** {F17833} The [sqlite3_blob_close(P)] interface closes an
**          [sqlite3_blob] object P previously opened using
**          [sqlite3_blob_open()].
**
** {F17836} Closing an [sqlite3_blob] object using
**          [sqlite3_blob_close()] shall cause the current transaction to
**          commit if there are no other open [sqlite3_blob] objects
**          or [prepared statements] on the same [database connection] and
**          the [database connection] is in
**          [sqlite3_get_autocommit | autocommit mode].
**
** {F17839} The [sqlite3_blob_close(P)] interfaces closes the 
**          [sqlite3_blob] object P unconditionally, even if
**          [sqlite3_blob_close(P)] returns something other than [SQLITE_OK].
**          
*/
int sqlite3_blob_close(sqlite3_blob *);

/*
** CAPI3REF:  Return The Size Of An Open BLOB {F17840}
**
** Return the size in bytes of the blob accessible via the open 
** [sqlite3_blob] object in its only argument.
**
** INVARIANTS:
**
** {F17843} The [sqlite3_blob_bytes(P)] interface returns the size
**          in bytes of the BLOB that the [sqlite3_blob] object P
**          refers to.
*/
int sqlite3_blob_bytes(sqlite3_blob *);

/*
** CAPI3REF:  Read Data From A BLOB Incrementally {F17850}
**
** This function is used to read data from an open 
** [sqlite3_blob | blob-handle] into a caller supplied buffer.
** N bytes of data are copied into buffer
** Z from the open blob, starting at offset iOffset.
**
** If offset iOffset is less than N bytes from the end of the blob, 
** [SQLITE_ERROR] is returned and no data is read.  If N or iOffset is
** less than zero [SQLITE_ERROR] is returned and no data is read.
**
** On success, SQLITE_OK is returned. Otherwise, an 
** [error code] or an [extended error code] is returned.
**
** INVARIANTS:
**
** {F17853} The [sqlite3_blob_read(P,Z,N,X)] interface reads N bytes
**          beginning at offset X from
**          the blob that [sqlite3_blob] object P refers to
**          and writes those N bytes into buffer Z.
**
** {F17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the blob
**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
**          and nothing is read from the blob.
**
** {F17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero
**          then the function returns [SQLITE_ERROR]
**          and nothing is read from the blob.
**
** {F17862} The [sqlite3_blob_read(P,Z,N,X)] interface returns [SQLITE_OK]
**          if N bytes where successfully read into buffer Z.
**
** {F17865} If the requested read could not be completed,
**          the [sqlite3_blob_read(P,Z,N,X)] interface returns an
**          appropriate [error code] or [extended error code].
**
** {F17868} If an error occurs during evaluation of [sqlite3_blob_read(D,...)]
**          then subsequent calls to [sqlite3_errcode(D)],
**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
**          information approprate for that error.
*/
int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);

/*
** CAPI3REF:  Write Data Into A BLOB Incrementally {F17870}
**
** This function is used to write data into an open 
** [sqlite3_blob | blob-handle] from a user supplied buffer.
** n bytes of data are copied from the buffer
** pointed to by z into the open blob, starting at offset iOffset.
**
** If the [sqlite3_blob | blob-handle] passed as the first argument
** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
*** was zero), this function returns [SQLITE_READONLY].
**
** This function may only modify the contents of the blob; it is
** not possible to increase the size of a blob using this API.
** If offset iOffset is less than n bytes from the end of the blob, 
** [SQLITE_ERROR] is returned and no data is written.  If n is
** less than zero [SQLITE_ERROR] is returned and no data is written.
**
** On success, SQLITE_OK is returned. Otherwise, an 
** [error code] or an [extended error code] is returned.
**
** INVARIANTS:
**
** {F17873} The [sqlite3_blob_write(P,Z,N,X)] interface writes N bytes
**          from buffer Z into
**          the blob that [sqlite3_blob] object P refers to
**          beginning at an offset of X into the blob.
**
** {F17875} The [sqlite3_blob_write(P,Z,N,X)] interface returns
**          [SQLITE_READONLY] if the [sqlite3_blob] object P was
**          [sqlite3_blob_open | opened] for reading only.
**
** {F17876} In [sqlite3_blob_write(P,Z,N,X)] if the size of the blob
**          is less than N+X bytes, then the function returns [SQLITE_ERROR]
**          and nothing is written into the blob.
**
** {F17879} In [sqlite3_blob_write(P,Z,N,X)] if X or N is less than zero
**          then the function returns [SQLITE_ERROR]
**          and nothing is written into the blob.
**
** {F17882} The [sqlite3_blob_write(P,Z,N,X)] interface returns [SQLITE_OK]
**          if N bytes where successfully written into blob.
**
** {F17885} If the requested write could not be completed,
**          the [sqlite3_blob_write(P,Z,N,X)] interface returns an
**          appropriate [error code] or [extended error code].
**
** {F17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)]
**          then subsequent calls to [sqlite3_errcode(D)],
**          [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return
**          information approprate for that error.
*/
int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);

/*
** CAPI3REF:  Virtual File System Objects {F11200}
**
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
** that SQLite uses to interact
** with the underlying operating system.  Most SQLite builds come with a
** single default VFS that is appropriate for the host computer.
** New VFSes can be registered and existing VFSes can be unregistered.
** The following interfaces are provided.
**
** The sqlite3_vfs_find() interface returns a pointer to 
** a VFS given its name.  Names are case sensitive.
** Names are zero-terminated UTF-8 strings.
** If there is no match, a NULL
** pointer is returned.  If zVfsName is NULL then the default 
** VFS is returned. 
**
** New VFSes are registered with sqlite3_vfs_register().
** Each new VFS becomes the default VFS if the makeDflt flag is set.
** The same VFS can be registered multiple times without injury.
** To make an existing VFS into the default VFS, register it again
** with the makeDflt flag set.  If two different VFSes with the
** same name are registered, the behavior is undefined.  If a
** VFS is registered with a name that is NULL or an empty string,
** then the behavior is undefined.
** 
** Unregister a VFS with the sqlite3_vfs_unregister() interface.
** If the default VFS is unregistered, another VFS is chosen as
** the default.  The choice for the new VFS is arbitrary.
**
** INVARIANTS:
**
** {F11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the
**          registered [sqlite3_vfs] object whose name exactly matches
**          the zero-terminated UTF-8 string N, or it returns NULL if
**          there is no match.
**
** {F11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then
**          the function returns a pointer to the default [sqlite3_vfs]
**          object if there is one, or NULL if there is no default 
**          [sqlite3_vfs] object.
**
** {F11209} The [sqlite3_vfs_register(P,F)] interface registers the
**          well-formed [sqlite3_vfs] object P using the name given
**          by the zName field of the object.
**
** {F11212} Using the [sqlite3_vfs_register(P,F)] interface to register
**          the same [sqlite3_vfs] object multiple times is a harmless no-op.
**
** {F11215} The [sqlite3_vfs_register(P,F)] interface makes the
**          the [sqlite3_vfs] object P the default [sqlite3_vfs] object
**          if F is non-zero.
**
** {F11218} The [sqlite3_vfs_unregister(P)] interface unregisters the
**          [sqlite3_vfs] object P so that it is no longer returned by
**          subsequent calls to [sqlite3_vfs_find()].
*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
int sqlite3_vfs_unregister(sqlite3_vfs*);

/*
** CAPI3REF: Mutexes {F17000}