text: /*
  ** 2001 September 15
  **
  ** The author disclaims copyright to this source code.  In place of
  ** a legal notice, here is a blessing:
  **
  **    May you do good and not evil.
  **    May you find forgiveness for yourself and forgive others.
  **    May you share freely, never taking more than you give.
  **
  *************************************************************************
  ** This header file defines the interface that the SQLite library
  ** presents to client programs.
  **
  ** @(#) $Id: sqlite.h.in,v 1.194 2006/09/16 21:45:14 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++.
  */
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /*
  ** The version of the SQLite library.
  */
  #ifdef SQLITE_VERSION
  # undef SQLITE_VERSION
  #endif
  #define SQLITE_VERSION         "3.3.8"
  
  /*
  ** The format of the version string is "X.Y.Z<trailing string>", where
  ** X is the major version number, Y is the minor version number and Z
  ** is the release number. The trailing string is often "alpha" or "beta".
  ** For example "3.1.1beta".
  **
  ** The SQLITE_VERSION_NUMBER is an integer with the value 
  ** (X*100000 + Y*1000 + Z). For example, for version "3.1.1beta", 
  ** SQLITE_VERSION_NUMBER is set to 3001001. To detect if they are using 
  ** version 3.1.1 or greater at compile time, programs may use the test 
  ** (SQLITE_VERSION_NUMBER>=3001001).
  */
  #ifdef SQLITE_VERSION_NUMBER
  # undef SQLITE_VERSION_NUMBER
  #endif
  #define SQLITE_VERSION_NUMBER 3003008
  
  /*
  ** The version string is also compiled into the library so that a program
  ** can check to make sure that the lib*.a file and the *.h file are from
  ** the same version.  The sqlite3_libversion() function returns a pointer
  ** to the sqlite3_version variable - useful in DLLs which cannot access
  ** global variables.
  */
  extern const char sqlite3_version[];
  const char *sqlite3_libversion(void);
  
  /*
  ** Return the value of the SQLITE_VERSION_NUMBER macro when the
  ** library was compiled.
  */
  int sqlite3_libversion_number(void);
  
  /*
  ** Each open sqlite database is represented by an instance of the
  ** following opaque structure.
  */
  typedef struct sqlite3 sqlite3;
  
  
  /*
  ** Some compilers do not support the "long long" datatype.  So we have
  ** to do a typedef that for 64-bit integers that depends on what compiler
  ** is being used.
  */
  #ifdef SQLITE_INT64_TYPE
    typedef SQLITE_INT64_TYPE sqlite_int64;
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
  #elif defined(_MSC_VER) || defined(__BORLANDC__)
    typedef __int64 sqlite_int64;
    typedef unsigned __int64 sqlite_uint64;
  #else
    typedef long long int sqlite_int64;
    typedef unsigned long long int sqlite_uint64;
  #endif
  
  /*
  ** If compiling for a processor that lacks floating point support,
  ** substitute integer for floating-point
  */
  #ifdef SQLITE_OMIT_FLOATING_POINT
  # define double sqlite_int64
  #endif
  
  /*
  ** A function to close the database.
  **
  ** Call this function with a pointer to a structure that was previously
  ** returned from sqlite3_open() and the corresponding database will by closed.
  **
  ** All SQL statements prepared using sqlite3_prepare() or
  ** sqlite3_prepare16() must be deallocated using sqlite3_finalize() before
  ** this routine is called. Otherwise, SQLITE_BUSY is returned and the
  ** database connection remains open.
  */
  int sqlite3_close(sqlite3 *);
  
  /*
  ** The type for a callback function.
  */
  typedef int (*sqlite3_callback)(void*,int,char**, char**);
  
  /*
  ** A function to executes one or more statements of SQL.
  **
  ** If one or more of the SQL statements are queries, then
  ** the callback function specified by the 3rd parameter is
  ** invoked once for each row of the query result.  This callback
  ** should normally return 0.  If the callback returns a non-zero
  ** value then the query is aborted, all subsequent SQL statements
  ** are skipped and the sqlite3_exec() function returns the SQLITE_ABORT.
  **
  ** The 4th parameter is an arbitrary pointer that is passed
  ** to the callback function as its first parameter.
  **
  ** The 2nd parameter to the callback function is the number of
  ** columns in the query result.  The 3rd parameter to the callback
  ** is an array of strings holding the values for each column.
  ** The 4th parameter to the callback is an array of strings holding
  ** the names of each column.
  **
  ** The callback function may be NULL, even for queries.  A NULL
  ** callback is not an error.  It just means that no callback
  ** will be invoked.
  **
  ** If an error occurs while parsing or evaluating the SQL (but
  ** not while executing the callback) then an appropriate error
  ** message is written into memory obtained from malloc() and
  ** *errmsg is made to point to that message.  The calling function
  ** is responsible for freeing the memory that holds the error
  ** message.   Use sqlite3_free() for this.  If errmsg==NULL,
  ** then no error message is ever written.
  **
  ** The return value is is SQLITE_OK if there are no errors and
  ** some other return code if there is an error.  The particular
  ** return value depends on the type of error. 
  **
  ** If the query could not be executed because a database file is
  ** locked or busy, then this function returns SQLITE_BUSY.  (This
  ** behavior can be modified somewhat using the sqlite3_busy_handler()
  ** and sqlite3_busy_timeout() functions below.)
  */
  int sqlite3_exec(
    sqlite3*,                     /* An open database */
    const char *sql,              /* SQL to be executed */
    sqlite3_callback,             /* Callback function */
    void *,                       /* 1st argument to callback function */
    char **errmsg                 /* Error msg written here */
  );
  
  /*
  ** Return values for sqlite3_exec() and sqlite3_step()
  */
  #define SQLITE_OK           0   /* Successful result */
  /* beginning-of-error-codes */
  #define SQLITE_ERROR        1   /* SQL error or missing database */
  #define SQLITE_INTERNAL     2   /* NOT USED. Internal logic error in SQLite */
  #define SQLITE_PERM         3   /* Access permission denied */
  #define SQLITE_ABORT        4   /* Callback routine requested an abort */
  #define SQLITE_BUSY         5   /* The database file is locked */
  #define SQLITE_LOCKED       6   /* A table in the database is locked */
  #define SQLITE_NOMEM        7   /* A malloc() failed */
  #define SQLITE_READONLY     8   /* Attempt to write a readonly database */
  #define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
  #define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
  #define SQLITE_CORRUPT     11   /* The database disk image is malformed */
  #define SQLITE_NOTFOUND    12   /* NOT USED. Table or record not found */
  #define SQLITE_FULL        13   /* Insertion failed because database is full */
  #define SQLITE_CANTOPEN    14   /* Unable to open the database file */
  #define SQLITE_PROTOCOL    15   /* Database lock protocol error */
  #define SQLITE_EMPTY       16   /* Database is empty */
  #define SQLITE_SCHEMA      17   /* The database schema changed */
  #define SQLITE_TOOBIG      18   /* NOT USED. Too much data for one row */
  #define SQLITE_CONSTRAINT  19   /* Abort due to contraint violation */
  #define SQLITE_MISMATCH    20   /* Data type mismatch */
  #define SQLITE_MISUSE      21   /* Library used incorrectly */
  #define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
  #define SQLITE_AUTH        23   /* Authorization denied */
  #define SQLITE_FORMAT      24   /* Auxiliary database format error */
  #define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
  #define SQLITE_NOTADB      26   /* File opened that is not a database file */
  #define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
  #define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
  /* end-of-error-codes */
  
  /*
  ** Using the sqlite3_extended_result_codes() API, you can cause
  ** SQLite to return result codes with additional information in
  ** their upper bits.  The lower 8 bits will be the same as the
  ** primary result codes above.  But the upper bits might contain
  ** more specific error information.
  **
  ** To extract the primary result code from an extended result code,
  ** simply mask off the lower 8 bits.
  **
  **        primary = extended & 0xff;
  **
  ** New result error codes may be added from time to time.  Software
  ** that uses the extended result codes should plan accordingly and be
  ** sure to always handle new unknown codes gracefully.
  **
  ** The SQLITE_OK result code will never be extended.  It will always
  ** be exactly zero.
  **
  ** The extended result codes always have the primary result code
  ** as a prefix.  Primary result codes only contain a single "_"
  ** character.  Extended result codes contain two or more "_" characters.
  */
  #define SQLITE_IOERR_READ          (SQLITE_IOERR | (1<<8))
  #define SQLITE_IOERR_SHORT_READ    (SQLITE_IOERR | (2<<8))
  #define SQLITE_IOERR_WRITE         (SQLITE_IOERR | (3<<8))
  #define SQLITE_IOERR_FSYNC         (SQLITE_IOERR | (4<<8))
  #define SQLITE_IOERR_DIR_FSYNC     (SQLITE_IOERR | (5<<8))
  #define SQLITE_IOERR_TRUNCATE      (SQLITE_IOERR | (6<<8))
  #define SQLITE_IOERR_FSTAT         (SQLITE_IOERR | (7<<8))
  #define SQLITE_IOERR_UNLOCK        (SQLITE_IOERR | (8<<8))
  #define SQLITE_IOERR_RDLOCK        (SQLITE_IOERR | (9<<8))
  
  /*
  ** Enable or disable the extended result codes.
  */
  int sqlite3_extended_result_codes(sqlite3*, int onoff);
  
  /*
  ** Each entry in an SQLite table has a unique integer key.  (The key is
  ** the value of the INTEGER PRIMARY KEY column if there is such a column,
  ** otherwise the key is generated at random.  The unique key is always
  ** available as the ROWID, OID, or _ROWID_ column.)  The following routine
  ** returns the integer key of the most recent insert in the database.
  **
  ** This function is similar to the mysql_insert_id() function from MySQL.
  */
  sqlite_int64 sqlite3_last_insert_rowid(sqlite3*);
  
  /*
  ** This function returns the number of database rows that were changed
  ** (or inserted or deleted) by the most recent called sqlite3_exec().
  **
  ** All changes are counted, even if they were later undone by a
  ** ROLLBACK or ABORT.  Except, changes associated with creating and
  ** dropping tables are not counted.
  **
  ** If a callback invokes sqlite3_exec() recursively, then the changes
  ** in the inner, recursive call are counted together with the changes
  ** in the outer call.
  **
  ** SQLite implements the command "DELETE FROM table" without a WHERE clause
  ** by dropping and recreating the table.  (This is much faster than going
  ** through and deleting individual elements form the table.)  Because of
  ** this optimization, the change count for "DELETE FROM table" will be
  ** zero regardless of the number of elements that were originally in the
  ** table. To get an accurate count of the number of rows deleted, use
  ** "DELETE FROM table WHERE 1" instead.
  */
  int sqlite3_changes(sqlite3*);
  
  /*
  ** This function returns the number of database rows that have been
  ** modified by INSERT, UPDATE or DELETE statements since the database handle
  ** was opened. This includes UPDATE, INSERT and DELETE statements executed
  ** as part of trigger programs. All changes are counted as soon as the
  ** statement that makes them is completed (when the statement handle is
  ** passed to sqlite3_reset() or sqlite_finalise()).
  **
  ** SQLite implements the command "DELETE FROM table" without a WHERE clause
  ** by dropping and recreating the table.  (This is much faster than going
  ** through and deleting individual elements form the table.)  Because of
  ** this optimization, the change count for "DELETE FROM table" will be
  ** zero regardless of the number of elements that were originally in the
  ** table. To get an accurate count of the number of rows deleted, use
  ** "DELETE FROM table WHERE 1" instead.
  */
  int sqlite3_total_changes(sqlite3*);
  
  /* This function causes any pending database operation to abort and
  ** return at its earliest opportunity.  This routine is typically
  ** called in response to a user action such as pressing "Cancel"
  ** or Ctrl-C where the user wants a long query operation to halt
  ** immediately.
  */
  void sqlite3_interrupt(sqlite3*);
  
  
  /* These functions return true if the given input string comprises
  ** one or more complete SQL statements. For the sqlite3_complete() call,
  ** the parameter must be a nul-terminated UTF-8 string. For
  ** sqlite3_complete16(), a nul-terminated machine byte order UTF-16 string
  ** is required.
  **
  ** The algorithm is simple.  If the last token other than spaces
  ** and comments is a semicolon, then return true.  otherwise return
  ** false.
  */
  int sqlite3_complete(const char *sql);
  int sqlite3_complete16(const void *sql);
  
  /*
  ** This routine identifies a callback function that is invoked
  ** whenever an attempt is made to open a database table that is
  ** currently locked by another process or thread.  If the busy callback
  ** is NULL, then sqlite3_exec() returns SQLITE_BUSY immediately if
  ** it finds a locked table.  If the busy callback is not NULL, then
  ** sqlite3_exec() invokes the callback with three arguments.  The
  ** second argument is the name of the locked table and the third
  ** argument is the number of times the table has been busy.  If the
  ** busy callback returns 0, then sqlite3_exec() immediately returns
  ** SQLITE_BUSY.  If the callback returns non-zero, then sqlite3_exec()
  ** tries to open the table again and the cycle repeats.
  **
  ** The default busy callback is NULL.
  **
  ** Sqlite is re-entrant, so the busy handler may start a new query. 
  ** (It is not clear why anyone would every want to do this, but it
  ** is allowed, in theory.)  But the busy handler may not close the
  ** database.  Closing the database from a busy handler will delete 
  ** data structures out from under the executing query and will 
  ** probably result in a coredump.
  */
  int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
  
  /*
  ** This routine sets a busy handler that sleeps for a while when a
  ** table is locked.  The handler will sleep multiple times until 
  ** at least "ms" milleseconds of sleeping have been done.  After
  ** "ms" milleseconds of sleeping, the handler returns 0 which
  ** causes sqlite3_exec() to return SQLITE_BUSY.
  **
  ** Calling this routine with an argument less than or equal to zero
  ** turns off all busy handlers.
  */
  int sqlite3_busy_timeout(sqlite3*, int ms);
  
  /*
  ** This next routine is really just a wrapper around sqlite3_exec().
  ** Instead of invoking a user-supplied callback for each row of the
  ** result, this routine remembers each row of the result in memory
  ** obtained from malloc(), then returns all of the result after the
  ** query has finished. 
  **
  ** As an example, suppose the query result where this table:
  **
  **        Name        | Age
  **        -----------------------
  **        Alice       | 43
  **        Bob         | 28
  **        Cindy       | 21
  **
  ** If the 3rd argument were &azResult then after the function returns
  ** azResult will contain the following data:
  **
  **        azResult[0] = "Name";
  **        azResult[1] = "Age";
  **        azResult[2] = "Alice";
  **        azResult[3] = "43";
  **        azResult[4] = "Bob";
  **        azResult[5] = "28";
  **        azResult[6] = "Cindy";
  **        azResult[7] = "21";
  **
  ** Notice that there is an extra row of data containing the column
  ** headers.  But the *nrow return value is still 3.  *ncolumn is
  ** set to 2.  In general, the number of values inserted into azResult
  ** will be ((*nrow) + 1)*(*ncolumn).
  **
  ** After the calling function has finished using the result, it should 
  ** pass the result data pointer to sqlite3_free_table() in order to 
  ** release the memory that was malloc-ed.  Because of the way the 
  ** malloc() happens, the calling function must not try to call 
  ** free() directly.  Only sqlite3_free_table() is able to release 
  ** the memory properly and safely.
  **
  ** The return value of this routine is the same as from sqlite3_exec().
  */
  int sqlite3_get_table(
    sqlite3*,               /* An open database */
    const char *sql,       /* SQL to be executed */
    char ***resultp,       /* Result written to a char *[]  that this points to */
    int *nrow,             /* Number of result rows written here */
    int *ncolumn,          /* Number of result columns written here */
    char **errmsg          /* Error msg written here */
  );
  
  /*
  ** Call this routine to free the memory that sqlite3_get_table() allocated.
  */
  void sqlite3_free_table(char **result);
  
  /*
  ** The following routines are variants of the "sprintf()" from the
  ** standard C library.  The resulting string is written into memory
  ** obtained from malloc() so that there is never a possiblity of buffer
  ** overflow.  These routines also implement some additional formatting
  ** options that are useful for constructing SQL statements.
  **
  ** The strings returned by these routines should be freed by calling
  ** sqlite3_free().
  **
  ** All of the usual printf formatting options apply.  In addition, there
  ** is a "%q" option.  %q works like %s in that it substitutes a null-terminated
  ** string from the argument list.  But %q also doubles every '\'' character.
  ** %q is designed for use inside a string literal.  By doubling each '\''
  ** character it escapes that character and allows it to be inserted into
  ** the string.
  **
  ** For example, so some string variable contains text as follows:
  **
  **      char *zText = "It's a happy day!";
  **
  ** We can use this text in an SQL statement as follows:
  **
  **      char *z = sqlite3_mprintf("INSERT INTO TABLES('%q')", zText);
  **      sqlite3_exec(db, z, callback1, 0, 0);
  **      sqlite3_free(z);
  **
  ** Because the %q format string is used, the '\'' character in zText
  ** is escaped and the SQL generated is as follows:
  **
  **      INSERT INTO table1 VALUES('It''s a happy day!')
  **
  ** This is correct.  Had we used %s instead of %q, the generated SQL
  ** would have looked like this:
  **
  **      INSERT INTO table1 VALUES('It's a happy day!');
  **
  ** This second example is an SQL syntax error.  As a general rule you
  ** should always use %q instead of %s when inserting text into a string 
  ** literal.
  */
  char *sqlite3_mprintf(const char*,...);
  char *sqlite3_vmprintf(const char*, va_list);
  char *sqlite3_snprintf(int,char*,const char*, ...);
  
  /*
  ** SQLite uses its own memory allocator.  On many installations, this
  ** memory allocator is identical to the standard malloc()/realloc()/free()
  ** and can be used interchangable.  On others, the implementations are
  ** different.  For maximum portability, it is best not to mix calls
  ** to the standard malloc/realloc/free with the sqlite versions.
  */
  void *sqlite3_malloc(int);
  void *sqlite3_realloc(void*, int);
  void sqlite3_free(void*);
  
  #ifndef SQLITE_OMIT_AUTHORIZATION
  /*
  ** This routine registers a callback with the SQLite library.  The
  ** callback is invoked (at compile-time, not at run-time) for each
  ** attempt to access a column of a table in the database.  The callback
  ** returns SQLITE_OK if access is allowed, SQLITE_DENY if the entire
  ** SQL statement should be aborted with an error and SQLITE_IGNORE
  ** if the column should be treated as a NULL value.
  */
  int sqlite3_set_authorizer(
    sqlite3*,
    int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
    void *pUserData
  );
  #endif
  
  /*
  ** The second parameter to the access authorization function above will
  ** be one of the values below.  These values signify what kind of operation
  ** is to be authorized.  The 3rd and 4th parameters to the authorization
  ** function will be parameters or NULL depending on which of the following
  ** codes is used as the second parameter.  The 5th parameter is the name
  ** of the database ("main", "temp", etc.) if applicable.  The 6th parameter
  ** is the name of the inner-most trigger or view that is responsible for
  ** the access attempt or NULL if this access attempt is directly from 
  ** input SQL code.
  **
  **                                          Arg-3           Arg-4
  */
  #define SQLITE_COPY                  0   /* Table Name      File Name       */
  #define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
  #define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
  #define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
  #define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
  #define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
  #define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
  #define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
  #define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
  #define SQLITE_DELETE                9   /* Table Name      NULL            */
  #define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
  #define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
  #define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
  #define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
  #define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
  #define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
  #define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
  #define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
  #define SQLITE_INSERT               18   /* Table Name      NULL            */
  #define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
  #define SQLITE_READ                 20   /* Table Name      Column Name     */
  #define SQLITE_SELECT               21   /* NULL            NULL            */
  #define SQLITE_TRANSACTION          22   /* NULL            NULL            */
  #define SQLITE_UPDATE               23   /* Table Name      Column Name     */
  #define SQLITE_ATTACH               24   /* Filename        NULL            */
  #define SQLITE_DETACH               25   /* Database Name   NULL            */
  #define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
  #define SQLITE_REINDEX              27   /* Index Name      NULL            */
  #define SQLITE_ANALYZE              28   /* Table Name      NULL            */
  #define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
  #define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
  #define SQLITE_FUNCTION             31   /* Function Name   NULL            */
  
  /*
  ** The return value of the authorization function should be one of the
  ** following constants:
  */
  /* #define SQLITE_OK  0   // Allow access (This is actually defined above) */
  #define SQLITE_DENY   1   /* Abort the SQL statement with an error */
  #define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
  
  /*
  ** Register a function for tracing SQL command evaluation.  The function
  ** registered by sqlite3_trace() is invoked at the first sqlite3_step()
  ** for the evaluation of an SQL statement.  The function registered by
  ** sqlite3_profile() runs at the end of each SQL statement and includes
  ** information on how long that statement ran.
  **
  ** The sqlite3_profile() API is currently considered experimental and
  ** is subject to change.
  */
  void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
  void *sqlite3_profile(sqlite3*,
     void(*xProfile)(void*,const char*,sqlite_uint64), void*);
  
  /*
  ** This routine configures a callback function - the progress callback - that
  ** is invoked periodically during long running calls to sqlite3_exec(),
  ** sqlite3_step() and sqlite3_get_table(). An example use for this API is to 
  ** keep a GUI updated during a large query.
  **
  ** The progress callback is invoked once for every N virtual machine opcodes,
  ** where N is the second argument to this function. The progress callback
  ** itself is identified by the third argument to this function. The fourth
  ** argument to this function is a void pointer passed to the progress callback
  ** function each time it is invoked.
  **
  ** If a call to sqlite3_exec(), sqlite3_step() or sqlite3_get_table() results 
  ** in less than N opcodes being executed, then the progress callback is not
  ** invoked.
  ** 
  ** To remove the progress callback altogether, pass NULL as the third
  ** argument to this function.
  **
  ** If the progress callback returns a result other than 0, then the current 
  ** query is immediately terminated and any database changes rolled back. If the
  ** query was part of a larger transaction, then the transaction is not rolled
  ** back and remains active. The sqlite3_exec() call returns SQLITE_ABORT. 
  **
  ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
  */
  void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
  
  /*
  ** Register a callback function to be invoked whenever a new transaction
  ** is committed.  The pArg argument is passed through to the callback.
  ** callback.  If the callback function returns non-zero, then the commit
  ** is converted into a rollback.
  **
  ** If another function was previously registered, its pArg value is returned.
  ** Otherwise NULL is returned.
  **
  ** Registering a NULL function disables the callback.
  **
  ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
  */
  void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
  
  /*
  ** Open the sqlite database file "filename".  The "filename" is UTF-8
  ** encoded for sqlite3_open() and UTF-16 encoded in the native byte order
  ** for sqlite3_open16().  An sqlite3* handle is returned in *ppDb, even
  ** if an error occurs. If the database is opened (or created) successfully,
  ** then SQLITE_OK is returned. Otherwise an error code is returned. The
  ** sqlite3_errmsg() or sqlite3_errmsg16()  routines can be used to obtain
  ** an English language description of the error.
  **
  ** If the database file does not exist, then a new database is created.
  ** The encoding for the database is UTF-8 if sqlite3_open() is called and
  ** UTF-16 if sqlite3_open16 is used.
  **
  ** Whether or not an error occurs when it is opened, resources associated
  ** with the sqlite3* handle should be released by passing it to
  ** sqlite3_close() when it is no longer required.
  */
  int sqlite3_open(
    const char *filename,   /* Database filename (UTF-8) */
    sqlite3 **ppDb          /* OUT: SQLite db handle */
  );
  int sqlite3_open16(
    const void *filename,   /* Database filename (UTF-16) */
    sqlite3 **ppDb          /* OUT: SQLite db handle */
  );
  
  /*
  ** Return the error code for the most recent sqlite3_* API call associated
  ** with sqlite3 handle 'db'. SQLITE_OK is returned if the most recent 
  ** API call was successful.
  **
  ** Calls to many sqlite3_* functions set the error code and string returned
  ** by sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16()
  ** (overwriting the previous values). Note that calls to sqlite3_errcode(),
  ** sqlite3_errmsg() and sqlite3_errmsg16() themselves do not affect the
  ** results of future invocations.
  **
  ** Assuming no other intervening sqlite3_* API calls are made, the error
  ** code returned by this function is associated with the same error as
  ** the strings  returned by sqlite3_errmsg() and sqlite3_errmsg16().
  */
  int sqlite3_errcode(sqlite3 *db);
  
  /*
  ** Return a pointer to a UTF-8 encoded string describing in english the
  ** error condition for the most recent sqlite3_* API call. The returned
  ** string is always terminated by an 0x00 byte.
  **
  ** The string "not an error" is returned when the most recent API call was
  ** successful.
  */
  const char *sqlite3_errmsg(sqlite3*);
  
  /*
  ** Return a pointer to a UTF-16 native byte order encoded string describing
  ** in english the error condition for the most recent sqlite3_* API call.
  ** The returned string is always terminated by a pair of 0x00 bytes.
  **
  ** The string "not an error" is returned when the most recent API call was
  ** successful.
  */
  const void *sqlite3_errmsg16(sqlite3*);
  
  /*
  ** An instance of the following opaque structure is used to represent
  ** a compiled SQL statment.
  */
  typedef struct sqlite3_stmt sqlite3_stmt;
  
  /*
  ** To execute an SQL query, it must first be compiled into a byte-code
  ** program using one of the following routines. The only difference between
  ** them is that the second argument, specifying the SQL statement to
  ** compile, is assumed to be encoded in UTF-8 for the sqlite3_prepare()
  ** function and UTF-16 for sqlite3_prepare16().
  **
  ** The first parameter "db" is an SQLite database handle. The second
  ** parameter "zSql" is the statement to be compiled, encoded as either
  ** UTF-8 or UTF-16 (see above). If the next parameter, "nBytes", is less
  ** than zero, then zSql is read up to the first nul terminator.  If
  ** "nBytes" is not less than zero, then it is the length of the string zSql
  ** in bytes (not characters).
  **
  ** *pzTail is made to point to the first byte past the end of the first
  ** SQL statement in zSql.  This routine only compiles the first statement
  ** in zSql, so *pzTail is left pointing to what remains uncompiled.
  **
  ** *ppStmt is left pointing to a compiled SQL statement that can be
  ** executed using sqlite3_step().  Or if there is an error, *ppStmt may be
  ** set to NULL.  If the input text contained no SQL (if the input is and
  ** empty string or a comment) then *ppStmt is set to NULL.
  **
  ** On success, SQLITE_OK is returned.  Otherwise an error code is returned.
  */
  int sqlite3_prepare(
    sqlite3 *db,            /* Database handle */
    const char *zSql,       /* SQL statement, UTF-8 encoded */
    int nBytes,             /* Length of zSql in bytes. */
    sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
    const char **pzTail     /* OUT: Pointer to unused portion of zSql */
  );
  int sqlite3_prepare16(
    sqlite3 *db,            /* Database handle */
    const void *zSql,       /* SQL statement, UTF-16 encoded */
    int nBytes,             /* Length of zSql in bytes. */
    sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
    const void **pzTail     /* OUT: Pointer to unused portion of zSql */
  );
  
  /*
  ** Pointers to the following two opaque structures are used to communicate
  ** with the implementations of user-defined functions.
  */
  typedef struct sqlite3_context sqlite3_context;
  typedef struct Mem sqlite3_value;
  
  /*
  ** In the SQL strings input to sqlite3_prepare() and sqlite3_prepare16(),
  ** one or more literals can be replace by parameters "?" or ":AAA" or
  ** "$VVV" where AAA is an identifer and VVV is a variable name according
  ** to the syntax rules of the TCL programming language.
  ** The value of these parameters (also called "host parameter names") can
  ** be set using the routines listed below.
  **
  ** In every case, the first parameter is a pointer to the sqlite3_stmt
  ** structure returned from sqlite3_prepare().  The second parameter is the
  ** index of the parameter.  The first parameter as an index of 1.  For
  ** named parameters (":AAA" or "$VVV") you can use 
  ** sqlite3_bind_parameter_index() to get the correct index value given
  ** the parameters name.  If the same named parameter occurs more than
  ** once, it is assigned the same index each time.
  **
  ** The fifth parameter to sqlite3_bind_blob(), sqlite3_bind_text(), and
  ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
  ** text after SQLite has finished with it.  If the fifth argument is the
  ** special value SQLITE_STATIC, then the library assumes that the information
  ** is in static, unmanaged space and does not need to be freed.  If the
  ** fifth argument has the value SQLITE_TRANSIENT, then SQLite makes its
  ** own private copy of the data.
  **
  ** The sqlite3_bind_* routine must be called before sqlite3_step() after
  ** an sqlite3_prepare() or sqlite3_reset().  Unbound parameterss are
  ** interpreted as NULL.
  */
  int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
  int sqlite3_bind_double(sqlite3_stmt*, int, double);
  int sqlite3_bind_int(sqlite3_stmt*, int, int);
  int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite_int64);
  int sqlite3_bind_null(sqlite3_stmt*, int);
  int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
  int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
  int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
  
  /*
  ** Return the number of parameters in a compiled SQL statement.  This
  ** routine was added to support DBD::SQLite.
  */
  int sqlite3_bind_parameter_count(sqlite3_stmt*);
  
  /*
  ** Return the name of the i-th parameter.  Ordinary parameters "?" are
  ** nameless and a NULL is returned.  For parameters of the form :AAA or
  ** $VVV the complete text of the parameter name is returned, including
  ** the initial ":" or "$".  NULL is returned if the index is out of range.
  */
  const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
  
  /*
  ** Return the index of a parameter with the given name.  The name
  ** must match exactly.  If no parameter with the given name is found,
  ** return 0.
  */
  int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
  
  /*
  ** Set all the parameters in the compiled SQL statement to NULL.
  */
  int sqlite3_clear_bindings(sqlite3_stmt*);
  
  /*
  ** Return the number of columns in the result set returned by the compiled
  ** SQL statement. This routine returns 0 if pStmt is an SQL statement
  ** that does not return data (for example an UPDATE).
  */
  int sqlite3_column_count(sqlite3_stmt *pStmt);
  
  /*
  ** The first parameter is a compiled SQL statement. This function returns
  ** the column heading for the Nth column of that statement, where N is the
  ** second function parameter.  The string returned is UTF-8 for
  ** sqlite3_column_name() and UTF-16 for sqlite3_column_name16().
  */
  const char *sqlite3_column_name(sqlite3_stmt*,int);
  const void *sqlite3_column_name16(sqlite3_stmt*,int);
  
  /*
  ** The first parameter to the following calls is a compiled SQL statement.
  ** These functions return information about the Nth column returned by 
  ** the statement, where N is the second function argument.
  **
  ** If the Nth column returned by the statement is not a column value,
  ** then all of the functions return NULL. Otherwise, the return the 
  ** name of the attached database, table and column that the expression
  ** extracts a value from.
  **
  ** As with all other SQLite APIs, those postfixed with "16" return UTF-16
  ** encoded strings, the other functions return UTF-8. The memory containing
  ** the returned strings is valid until the statement handle is finalized().
  **
  ** These APIs are only available if the library was compiled with the 
  ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
  */
  const char *sqlite3_column_database_name(sqlite3_stmt*,int);
  const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
  const char *sqlite3_column_table_name(sqlite3_stmt*,int);
  const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
  const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
  const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
  
  /*
  ** The first parameter is a compiled SQL statement. If this statement
  ** is a SELECT statement, the Nth column of the returned result set 
  ** of the SELECT is a table column then the declared type of the table
  ** column is returned. If the Nth column of the result set is not at table
  ** column, then a NULL pointer is returned. The returned string is always
  ** UTF-8 encoded. For example, in the database schema:
  **
  ** CREATE TABLE t1(c1 VARIANT);
  **
  ** And the following statement compiled:
  **
  ** SELECT c1 + 1, c1 FROM t1;
  **
  ** Then this routine would return the string "VARIANT" for the second
  ** result column (i==1), and a NULL pointer for the first result column
  ** (i==0).
  */
  const char *sqlite3_column_decltype(sqlite3_stmt *, int i);
  
  /*
  ** The first parameter is a compiled SQL statement. If this statement
  ** is a SELECT statement, the Nth column of the returned result set 
  ** of the SELECT is a table column then the declared type of the table
  ** column is returned. If the Nth column of the result set is not at table
  ** column, then a NULL pointer is returned. The returned string is always
  ** UTF-16 encoded. For example, in the database schema:
  **
  ** CREATE TABLE t1(c1 INTEGER);
  **
  ** And the following statement compiled:
  **
  ** SELECT c1 + 1, c1 FROM t1;
  **
  ** Then this routine would return the string "INTEGER" for the second
  ** result column (i==1), and a NULL pointer for the first result column
  ** (i==0).
  */
  const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
  
  /* 
  ** After an SQL query has been compiled with a call to either
  ** sqlite3_prepare() or sqlite3_prepare16(), then this function must be
  ** called one or more times to execute the statement.
  **
  ** The return value will be either SQLITE_BUSY, SQLITE_DONE, 
  ** SQLITE_ROW, SQLITE_ERROR, or SQLITE_MISUSE.
  **
  ** SQLITE_BUSY means that the database engine attempted to open
  ** a locked database and there is no busy callback registered.
  ** Call sqlite3_step() again to retry the open.
  **
  ** SQLITE_DONE means that the statement has finished executing
  ** successfully.  sqlite3_step() should not be called again on this virtual
  ** machine.
  **
  ** If the SQL statement being executed returns any data, then 
  ** SQLITE_ROW is returned each time a new row of data is ready
  ** for processing by the caller. The values may be accessed using
  ** the sqlite3_column_*() functions described below. sqlite3_step()
  ** is called again to retrieve the next row of data.
  ** 
  ** SQLITE_ERROR means that a run-time error (such as a constraint
  ** violation) has occurred.  sqlite3_step() should not be called again on
  ** the VM. More information may be found by calling sqlite3_errmsg().
  **
  ** SQLITE_MISUSE means that the this routine was called inappropriately.
  ** Perhaps it was called on a virtual machine that had already been
  ** finalized or on one that had previously returned SQLITE_ERROR or
  ** SQLITE_DONE.  Or it could be the case the the same database connection
  ** is being used simulataneously by two or more threads.
  */
  int sqlite3_step(sqlite3_stmt*);
  
  /*
  ** Return the number of values in the current row of the result set.
  **
  ** After a call to sqlite3_step() that returns SQLITE_ROW, this routine
  ** will return the same value as the sqlite3_column_count() function.
  ** After sqlite3_step() has returned an SQLITE_DONE, SQLITE_BUSY or
  ** error code, or before sqlite3_step() has been called on a 
  ** compiled SQL statement, this routine returns zero.
  */
  int sqlite3_data_count(sqlite3_stmt *pStmt);
  
  /*
  ** Values are stored in the database in one of the following fundamental
  ** types.
  */
  #define SQLITE_INTEGER  1
  #define SQLITE_FLOAT    2
  /* #define SQLITE_TEXT  3  // See below */
  #define SQLITE_BLOB     4
  #define SQLITE_NULL     5
  
  /*
  ** SQLite version 2 defines SQLITE_TEXT differently.  To allow both
  ** version 2 and version 3 to be included, undefine them both if a
  ** conflict is seen.  Define SQLITE3_TEXT to be the version 3 value.
  */
  #ifdef SQLITE_TEXT
  # undef SQLITE_TEXT
  #else
  # define SQLITE_TEXT     3
  #endif
  #define SQLITE3_TEXT     3
  
  /*
  ** The next group of routines returns information about the information
  ** in a single column of the current result row of a query.  In every
  ** case the first parameter is a pointer to the SQL statement that is being
  ** executed (the sqlite_stmt* that was returned from sqlite3_prepare()) and
  ** the second argument is the index of the column for which information 
  ** should be returned.  iCol is zero-indexed.  The left-most column as an
  ** index of 0.
  **
  ** If the SQL statement is not currently point to a valid row, or if the
  ** the colulmn index is out of range, the result is undefined.
  **
  ** These routines attempt to convert the value where appropriate.  For
  ** example, if the internal representation is FLOAT and a text result
  ** is requested, sprintf() is used internally to do the conversion
  ** automatically.  The following table details the conversions that
  ** are applied:
  **
  **    Internal Type    Requested Type     Conversion
  **    -------------    --------------    --------------------------
  **       NULL             INTEGER         Result is 0
  **       NULL             FLOAT           Result is 0.0
  **       NULL             TEXT            Result is an empty string
  **       NULL             BLOB            Result is a zero-length BLOB
  **       INTEGER          FLOAT           Convert from integer to float
  **       INTEGER          TEXT            ASCII rendering of the integer
  **       INTEGER          BLOB            Same as for INTEGER->TEXT
  **       FLOAT            INTEGER         Convert from float to integer
  **       FLOAT            TEXT            ASCII rendering of the float
  **       FLOAT            BLOB            Same as FLOAT->TEXT
  **       TEXT             INTEGER         Use atoi()
  **       TEXT             FLOAT           Use atof()
  **       TEXT             BLOB            No change
  **       BLOB             INTEGER         Convert to TEXT then use atoi()
  **       BLOB             FLOAT           Convert to TEXT then use atof()
  **       BLOB             TEXT            Add a \000 terminator if needed
  **
  ** The following access routines are provided:
  **
  ** _type()     Return the datatype of the result.  This is one of
  **             SQLITE_INTEGER, SQLITE_FLOAT, SQLITE_TEXT, SQLITE_BLOB,
  **             or SQLITE_NULL.
  ** _blob()     Return the value of a BLOB.
  ** _bytes()    Return the number of bytes in a BLOB value or the number
  **             of bytes in a TEXT value represented as UTF-8.  The \000
  **             terminator is included in the byte count for TEXT values.
  ** _bytes16()  Return the number of bytes in a BLOB value or the number
  **             of bytes in a TEXT value represented as UTF-16.  The \u0000
  **             terminator is included in the byte count for TEXT values.
  ** _double()   Return a FLOAT value.
  ** _int()      Return an INTEGER value in the host computer's native
  **             integer representation.  This might be either a 32- or 64-bit
  **             integer depending on the host.
  ** _int64()    Return an INTEGER value as a 64-bit signed integer.
  ** _text()     Return the value as UTF-8 text.
  ** _text16()   Return the value as UTF-16 text.
  */
  const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
  int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
  int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
  double sqlite3_column_double(sqlite3_stmt*, int iCol);
  int sqlite3_column_int(sqlite3_stmt*, int iCol);
  sqlite_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
  const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
  const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
  int sqlite3_column_type(sqlite3_stmt*, int iCol);
  int sqlite3_column_numeric_type(sqlite3_stmt*, int iCol);
  sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
  
  /*
  ** The sqlite3_finalize() function is called to delete a compiled
  ** SQL statement obtained by a previous call to sqlite3_prepare()
  ** or sqlite3_prepare16(). If the statement was executed successfully, or
  ** not executed at all, then SQLITE_OK is returned. If execution of the
  ** statement failed then an error code is returned. 
  **
  ** This routine can be called at any point during the execution of the
  ** virtual machine.  If the virtual machine has not completed execution
  ** when this routine is called, that is like encountering an error or
  ** an interrupt.  (See sqlite3_interrupt().)  Incomplete updates may be
  ** rolled back and transactions cancelled,  depending on the circumstances,
  ** and the result code returned will be SQLITE_ABORT.
  */
  int sqlite3_finalize(sqlite3_stmt *pStmt);
  
  /*
  ** The sqlite3_reset() function is called to reset a compiled SQL
  ** statement obtained by a previous call to sqlite3_prepare() or
  ** sqlite3_prepare16() back to it's initial state, ready to be re-executed.
  ** Any SQL statement variables that had values bound to them using
  ** the sqlite3_bind_*() API retain their values.
  */
  int sqlite3_reset(sqlite3_stmt *pStmt);
  
  /*
  ** The following two functions are used to add user functions or aggregates
  ** implemented in C to the SQL langauge interpreted by SQLite. The
  ** difference only between the two is that the second parameter, the
  ** name of the (scalar) function or aggregate, is encoded in UTF-8 for
  ** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
  **
  ** The first argument is the database handle that the new function or
  ** aggregate is to be added to. If a single program uses more than one
  ** database handle internally, then user functions or aggregates must 
  ** be added individually to each database handle with which they will be
  ** used.
  **
  ** The third parameter is the number of arguments that the function or
  ** aggregate takes. If this parameter is negative, then the function or
  ** aggregate may take any number of arguments.
  **
  ** The fourth parameter is one of SQLITE_UTF* values defined below,
  ** indicating the encoding that the function is most likely to handle
  ** values in.  This does not change the behaviour of the programming
  ** interface. However, if two versions of the same function are registered
  ** with different encoding values, SQLite invokes the version likely to
  ** minimize conversions between text encodings.
  **
  ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
  ** pointers to user implemented C functions that implement the user
  ** function or aggregate. A scalar function requires an implementation of
  ** the xFunc callback only, NULL pointers should be passed as the xStep
  ** and xFinal parameters. An aggregate function requires an implementation
  ** of xStep and xFinal, but NULL should be passed for xFunc. To delete an
  ** existing user function or aggregate, pass NULL for all three function
  ** callback. Specifying an inconstent set of callback values, such as an
  ** xFunc and an xFinal, or an xStep but no xFinal, SQLITE_ERROR is
  ** returned.
  */
  int sqlite3_create_function(
    sqlite3 *,
    const char *zFunctionName,
    int nArg,
    int eTextRep,
    void*,
    void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
    void (*xStep)(sqlite3_context*,int,sqlite3_value**),
    void (*xFinal)(sqlite3_context*)
  );
  int sqlite3_create_function16(
    sqlite3*,
    const void *zFunctionName,
    int nArg,
    int eTextRep,
    void*,
    void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
    void (*xStep)(sqlite3_context*,int,sqlite3_value**),
    void (*xFinal)(sqlite3_context*)
  );
  
  /*
  ** This function is deprecated.  Do not use it.  It continues to exist
  ** so as not to break legacy code.  But new code should avoid using it.
  */
  int sqlite3_aggregate_count(sqlite3_context*);
  
  /*
  ** The next group of routines returns information about parameters to
  ** a user-defined function.  Function implementations use these routines
  ** to access their parameters.  These routines are the same as the
  ** sqlite3_column_* routines except that these routines take a single
  ** sqlite3_value* pointer instead of an sqlite3_stmt* and an integer
  ** column number.
  */
  const void *sqlite3_value_blob(sqlite3_value*);
  int sqlite3_value_bytes(sqlite3_value*);
  int sqlite3_value_bytes16(sqlite3_value*);
  double sqlite3_value_double(sqlite3_value*);
  int sqlite3_value_int(sqlite3_value*);
  sqlite_int64 sqlite3_value_int64(sqlite3_value*);
  const unsigned char *sqlite3_value_text(sqlite3_value*);
  const void *sqlite3_value_text16(sqlite3_value*);
  const void *sqlite3_value_text16le(sqlite3_value*);
  const void *sqlite3_value_text16be(sqlite3_value*);
  int sqlite3_value_type(sqlite3_value*);
  int sqlite3_value_numeric_type(sqlite3_value*);
  
  /*
  ** Aggregate functions use the following routine to allocate
  ** a structure for storing their state.  The first time this routine
  ** is called for a particular aggregate, a new structure of size nBytes
  ** is allocated, zeroed, and returned.  On subsequent calls (for the
  ** same aggregate instance) the same buffer is returned.  The implementation
  ** of the aggregate can use the returned buffer to accumulate data.
  **
  ** The buffer allocated is freed automatically by SQLite.
  */
  void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
  
  /*
  ** The pUserData parameter to the sqlite3_create_function()
  ** routine used to register user functions is available to
  ** the implementation of the function using this call.
  */
  void *sqlite3_user_data(sqlite3_context*);
  
  /*
  ** The following two functions may be used by scalar user functions to
  ** associate meta-data with argument values. If the same value is passed to
  ** multiple invocations of the user-function during query execution, under
  ** some circumstances the associated meta-data may be preserved. This may
  ** be used, for example, to add a regular-expression matching scalar
  ** function. The compiled version of the regular expression is stored as
  ** meta-data associated with the SQL value passed as the regular expression
  ** pattern.
  **
  ** Calling sqlite3_get_auxdata() returns a pointer to the meta data
  ** associated with the Nth argument value to the current user function
  ** call, where N is the second parameter. If no meta-data has been set for
  ** that value, then a NULL pointer is returned.
  **
  ** The sqlite3_set_auxdata() is used to associate meta data with a user
  ** function argument. The third parameter is a pointer to the meta data
  ** to be associated with the Nth user function argument value. The fourth
  ** parameter specifies a 'delete function' that will be called on the meta
  ** data pointer to release it when it is no longer required. If the delete
  ** function pointer is NULL, it is not invoked.
  **
  ** In practice, meta-data is preserved between function calls for
  ** expressions that are constant at compile time. This includes literal
  ** values and SQL variables.
  */
  void *sqlite3_get_auxdata(sqlite3_context*, int);
  void sqlite3_set_auxdata(sqlite3_context*, int, void*, void (*)(void*));
  
  
  /*
  ** These are special value for the destructor that is passed in as the
  ** final argument to routines like sqlite3_result_blob().  If the destructor
  ** argument is SQLITE_STATIC, it means that the content pointer is constant
  ** and will never change.  It does not need to be destroyed.  The 
  ** SQLITE_TRANSIENT value means that the content will likely change in
  ** the near future and that SQLite should make its own private copy of
  ** the content before returning.
  */
  #define SQLITE_STATIC      ((void(*)(void *))0)
  #define SQLITE_TRANSIENT   ((void(*)(void *))-1)
  
  /*
  ** User-defined functions invoke the following routines in order to
  ** set their return value.
  */
  void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
  void sqlite3_result_double(sqlite3_context*, double);
  void sqlite3_result_error(sqlite3_context*, const char*, int);
  void sqlite3_result_error16(sqlite3_context*, const void*, int);
  void sqlite3_result_int(sqlite3_context*, int);
  void sqlite3_result_int64(sqlite3_context*, sqlite_int64);
  void sqlite3_result_null(sqlite3_context*);
  void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
  void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
  void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
  void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
  void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
  
  /*
  ** These are the allowed values for the eTextRep argument to
  ** sqlite3_create_collation and sqlite3_create_function.
  */
  #define SQLITE_UTF8           1
  #define SQLITE_UTF16LE        2
  #define SQLITE_UTF16BE        3
  #define SQLITE_UTF16          4    /* Use native byte order */
  #define SQLITE_ANY            5    /* sqlite3_create_function only */
  #define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
  
  /*
  ** These two functions are used to add new collation sequences to the
  ** sqlite3 handle specified as the first argument. 
  **
  ** The name of the new collation sequence is specified as a UTF-8 string
  ** for sqlite3_create_collation() and a UTF-16 string for
  ** sqlite3_create_collation16(). In both cases the name is passed as the
  ** second function argument.
  **
  ** The third argument must be one of the constants SQLITE_UTF8,
  ** SQLITE_UTF16LE or SQLITE_UTF16BE, indicating that the user-supplied
  ** routine expects to be passed pointers to strings encoded using UTF-8,
  ** UTF-16 little-endian or UTF-16 big-endian respectively.
  **
  ** A pointer to the user supplied routine must be passed as the fifth
  ** argument. If it is NULL, this is the same as deleting the collation
  ** sequence (so that SQLite cannot call it anymore). Each time the user
  ** supplied function is invoked, it is passed a copy of the void* passed as
  ** the fourth argument to sqlite3_create_collation() or
  ** sqlite3_create_collation16() as its first parameter.
  **
  ** The remaining arguments to the user-supplied routine are two strings,
  ** each represented by a [length, data] pair and encoded in the encoding
  ** that was passed as the third argument when the collation sequence was
  ** registered. The user routine should return negative, zero or positive if
  ** the first string is less than, equal to, or greater than the second
  ** string. i.e. (STRING1 - STRING2).
  */
  int sqlite3_create_collation(
    sqlite3*, 
    const char *zName, 
    int eTextRep, 
    void*,
    int(*xCompare)(void*,int,const void*,int,const void*)
  );
  int sqlite3_create_collation16(
    sqlite3*, 
    const char *zName, 
    int eTextRep, 
    void*,
    int(*xCompare)(void*,int,const void*,int,const void*)
  );
  
  /*
  ** To avoid having to register all collation sequences before a database
  ** can be used, a single callback function may be registered with the
  ** database handle to be called whenever an undefined collation sequence is
  ** required.
  **
  ** If the function is registered using the sqlite3_collation_needed() API,
  ** then it is passed the names of undefined collation sequences as strings
  ** encoded in UTF-8. If sqlite3_collation_needed16() is used, the names
  ** are passed as UTF-16 in machine native byte order. A call to either
  ** function replaces any existing callback.
  **
  ** When the user-function is invoked, the first argument passed is a copy
  ** of the second argument to sqlite3_collation_needed() or
  ** sqlite3_collation_needed16(). The second argument is the database
  ** handle. The third argument is one of SQLITE_UTF8, SQLITE_UTF16BE or
  ** SQLITE_UTF16LE, indicating the most desirable form of the collation
  ** sequence function required. The fourth parameter is the name of the
  ** required collation sequence.
  **
  ** The collation sequence is returned to SQLite by a collation-needed
  ** callback using the sqlite3_create_collation() or
  ** sqlite3_create_collation16() APIs, described above.
  */
  int sqlite3_collation_needed(
    sqlite3*, 
    void*, 
    void(*)(void*,sqlite3*,int eTextRep,const char*)
  );
  int sqlite3_collation_needed16(
    sqlite3*, 
    void*,
    void(*)(void*,sqlite3*,int eTextRep,const void*)
  );
  
  /*
  ** Specify the key for an encrypted database.  This routine should be
  ** called right after sqlite3_open().
  **
  ** The code to implement this API is not available in the public release
  ** of SQLite.
  */
  int sqlite3_key(
    sqlite3 *db,                   /* Database to be rekeyed */
    const void *pKey, int nKey     /* The key */
  );
  
  /*
  ** Change the key on an open database.  If the current database is not
  ** encrypted, this routine will encrypt it.  If pNew==0 or nNew==0, the
  ** database is decrypted.
  **
  ** The code to implement this API is not available in the public release
  ** of SQLite.
  */
  int sqlite3_rekey(
    sqlite3 *db,                   /* Database to be rekeyed */
    const void *pKey, int nKey     /* The new key */
  );
  
  /*
  ** Sleep for a little while. The second parameter is the number of
  ** miliseconds to sleep for. 
  **
  ** If the operating system does not support sleep requests with 
  ** milisecond time resolution, then the time will be rounded up to 
  ** the nearest second. The number of miliseconds of sleep actually 
  ** requested from the operating system is returned.
  */
  int sqlite3_sleep(int);
  
  /*
  ** Return TRUE (non-zero) if the statement supplied as an argument needs
  ** to be recompiled.  A statement needs to be recompiled whenever the
  ** execution environment changes in a way that would alter the program
  ** that sqlite3_prepare() generates.  For example, if new functions or
  ** collating sequences are registered or if an authorizer function is
  ** added or changed.
  **
  */
  int sqlite3_expired(sqlite3_stmt*);
  
  /*
  ** Move all bindings from the first prepared statement over to the second.
  ** This routine is useful, for example, if the first prepared statement
  ** fails with an SQLITE_SCHEMA error.  The same SQL can be prepared into
  ** the second prepared statement then all of the bindings transfered over
  ** to the second statement before the first statement is finalized.
  */
  int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
  
  /*
  ** If the following global variable is made to point to a
  ** string which is the name of a directory, then all temporary files
  ** created by SQLite will be placed in that directory.  If this variable
  ** is NULL pointer, then SQLite does a search for an appropriate temporary
  ** file directory.
  **
  ** Once sqlite3_open() has been called, changing this variable will invalidate
  ** the current temporary database, if any.
  */
  extern char *sqlite3_temp_directory;
  
  /*
  ** This function is called to recover from a malloc() failure that occured
  ** within the SQLite library. Normally, after a single malloc() fails the 
  ** library refuses to function (all major calls return SQLITE_NOMEM).
  ** This function restores the library state so that it can be used again.
  **
  ** All existing statements (sqlite3_stmt pointers) must be finalized or
  ** reset before this call is made. Otherwise, SQLITE_BUSY is returned.
  ** If any in-memory databases are in use, either as a main or TEMP
  ** database, SQLITE_ERROR is returned. In either of these cases, the 
  ** library is not reset and remains unusable.
  **
  ** This function is *not* threadsafe. Calling this from within a threaded
  ** application when threads other than the caller have used SQLite is
  ** dangerous and will almost certainly result in malfunctions.
  **
  ** This functionality can be omitted from a build by defining the 
  ** SQLITE_OMIT_GLOBALRECOVER at compile time.
  */
  int sqlite3_global_recover(void);
  
  /*
  ** Test to see whether or not the database connection is in autocommit
  ** mode.  Return TRUE if it is and FALSE if not.  Autocommit mode is on
  ** by default.  Autocommit is disabled by a BEGIN statement and reenabled
  ** by the next COMMIT or ROLLBACK.
  */
  int sqlite3_get_autocommit(sqlite3*);
  
  /*
  ** Return the sqlite3* database handle to which the prepared statement given
  ** in the argument belongs.  This is the same database handle that was
  ** the first argument to the sqlite3_prepare() that was used to create
  ** the statement in the first place.
  */
  sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
  
  /*
  ** Register a callback function with the database connection identified by the 
  ** first argument to be invoked whenever a row is updated, inserted or deleted.
  ** Any callback set by a previous call to this function for the same 
  ** database connection is overridden.
  **
  ** The second argument is a pointer to the function to invoke when a 
  ** row is updated, inserted or deleted. The first argument to the callback is
  ** a copy of the third argument to sqlite3_update_hook. The second callback 
  ** argument is one of SQLITE_INSERT, SQLITE_DELETE or SQLITE_UPDATE, depending
  ** on the operation that caused the callback to be invoked. The third and 
  ** fourth arguments to the callback contain pointers to the database and 
  ** table name containing the affected row. The final callback parameter is 
  ** the rowid of the row. In the case of an update, this is the rowid after 
  ** the update takes place.
  **
  ** The update hook is not invoked when internal system tables are
  ** modified (i.e. sqlite_master and sqlite_sequence).
  **
  ** If another function was previously registered, its pArg value is returned.
  ** Otherwise NULL is returned.
  */
  void *sqlite3_update_hook(
    sqlite3*, 
    void(*)(void *,int ,char const *,char const *,sqlite_int64),
    void*
  );
  
  /*
  ** Register a callback to be invoked whenever a transaction is rolled
  ** back. 
  **
  ** The new callback function overrides any existing rollback-hook
  ** callback. If there was an existing callback, then it's pArg value 
  ** (the third argument to sqlite3_rollback_hook() when it was registered) 
  ** is returned. Otherwise, NULL is returned.
  **
  ** For the purposes of this API, a transaction is said to have been 
  ** rolled back if an explicit "ROLLBACK" statement is executed, or
  ** an error or constraint causes an implicit rollback to occur. The 
  ** callback is not invoked if a transaction is automatically rolled
  ** back because the database connection is closed.
  */
  void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
  
  /*
  ** This function is only available if the library is compiled without
  ** the SQLITE_OMIT_SHARED_CACHE macro defined. It is used to enable or
  ** disable (if the argument is true or false, respectively) the 
  ** "shared pager" feature.
  */
  int sqlite3_enable_shared_cache(int);
  
  /*
  ** Attempt to free N bytes of heap memory by deallocating non-essential
  ** memory allocations held by the database library (example: memory 
  ** used to cache database pages to improve performance).
  **
  ** This function is not a part of standard builds.  It is only created
  ** if SQLite is compiled with the SQLITE_ENABLE_MEMORY_MANAGEMENT macro.
  */
  int sqlite3_release_memory(int);
  
  /*
  ** Place a "soft" limit on the amount of heap memory that may be allocated by
  ** SQLite within the current thread. If an internal allocation is requested 
  ** that would exceed the specified limit, sqlite3_release_memory() is invoked
  ** one or more times to free up some space before the allocation is made.
  **
  ** The limit is called "soft", because if sqlite3_release_memory() cannot free
  ** sufficient memory to prevent the limit from being exceeded, the memory is
  ** allocated anyway and the current operation proceeds.
  **
  ** This function is only available if the library was compiled with the 
  ** SQLITE_ENABLE_MEMORY_MANAGEMENT option set.
  ** memory-management has been enabled.
  */
  void sqlite3_soft_heap_limit(int);
  
  /*
  ** This routine makes sure that all thread-local storage has been
  ** deallocated for the current thread.
  **
  ** This routine is not technically necessary.  All thread-local storage
  ** will be automatically deallocated once memory-management and
  ** shared-cache are disabled and the soft heap limit has been set
  ** to zero.  This routine is provided as a convenience for users who
  ** want to make absolutely sure they have not forgotten something
  ** prior to killing off a thread.
  */
  void sqlite3_thread_cleanup(void);
  
  /*
  ** Return meta information about a specific column of a specific database
  ** table accessible using the connection handle passed as the first function 
  ** argument.
  **
  ** The column is identified by the second, third and fourth parameters to 
  ** this function. The second parameter is either the name of the database
  ** (i.e. "main", "temp" or an attached database) containing the specified
  ** table or NULL. If it is NULL, then all attached databases are searched
  ** for the table using the same algorithm as the database engine uses to 
  ** resolve unqualified table references.
  **
  ** The third and fourth parameters to this function are the table and column 
  ** name of the desired column, respectively. Neither of these parameters 
  ** may be NULL.
  **
  ** Meta information is returned by writing to the memory locations passed as
  ** the 5th and subsequent parameters to this function. Any of these 
  ** arguments may be NULL, in which case the corresponding element of meta 
  ** information is ommitted.
  **
  ** Parameter     Output Type      Description
  ** -----------------------------------
  **
  **   5th         const char*      Data type
  **   6th         const char*      Name of the default collation sequence 
  **   7th         int              True if the column has a NOT NULL constraint
  **   8th         int              True if the column is part of the PRIMARY KEY
  **   9th         int              True if the column is AUTOINCREMENT
  **
  **
  ** The memory pointed to by the character pointers returned for the 
  ** declaration type and collation sequence is valid only until the next 
  ** call to any sqlite API function.
  **
  ** If the specified table is actually a view, then an error is returned.
  **
  ** If the specified column is "rowid", "oid" or "_rowid_" and an 
  ** INTEGER PRIMARY KEY column has been explicitly declared, then the output 
  ** parameters are set for the explicitly declared column. If there is no
  ** explicitly declared IPK column, then the output parameters are set as 
  ** follows:
  **
  **     data type: "INTEGER"
  **     collation sequence: "BINARY"
  **     not null: 0
  **     primary key: 1
  **     auto increment: 0
  **
  ** This function may load one or more schemas from database files. If an
  ** error occurs during this process, or if the requested table or column
  ** cannot be found, an SQLITE error code is returned and an error message
  ** left in the database handle (to be retrieved using sqlite3_errmsg()).
  **
  ** This API is only available if the library was compiled with the
  ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
  */
  int sqlite3_table_column_metadata(
    sqlite3 *db,                /* Connection handle */
    const char *zDbName,        /* Database name or NULL */
    const char *zTableName,     /* Table name */
    const char *zColumnName,    /* Column name */
    char const **pzDataType,    /* OUTPUT: Declared data type */
    char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
    int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
    int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
    int *pAutoinc               /* OUTPUT: True if colums is auto-increment */
  );
  
  /*
  ****** EXPERIMENTAL - subject to change without notice **************
  **
  ** Attempt to load an SQLite extension library contained in the file
  ** zFile.  The entry point is zProc.  zProc may be 0 in which case the
  ** name of the entry point defaults to "sqlite3_extension_init".
  **
  ** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
  **
  ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 
  ** error message text.  The calling function should free this memory
  ** by calling sqlite3_free().
  **
  ** Extension loading must be enabled using sqlite3_enable_load_extension()
  ** prior to calling this API or an error will be returned.
  **
  ****** EXPERIMENTAL - subject to change without notice **************
  */
  int sqlite3_load_extension(
    sqlite3 *db,          /* Load the extension into this database connection */
    const char *zFile,    /* Name of the shared library containing extension */
    const char *zProc,    /* Entry point.  Derived from zFile if 0 */
    char **pzErrMsg       /* Put error message here if not 0 */
  );
  
  /*
  ** So as not to open security holes in older applications that are
  ** unprepared to deal with extension load, and as a means of disabling
  ** extension loading while executing user-entered SQL, the following
  ** API is provided to turn the extension loading mechanism on and
  ** off.  It is off by default.  See ticket #1863.
  **
  ** Call this routine with onoff==1 to turn extension loading on
  ** and call it with onoff==0 to turn it back off again.
  */
  int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
  
  /*
  ****** EXPERIMENTAL - subject to change without notice **************
  **
  ** Register an extension entry point that is automatically invoked
  ** whenever a new database connection is opened.
  **
  ** This API can be invoked at program startup in order to register
  ** one or more statically linked extensions that will be available
  ** to all new database connections.
  **
  ** Duplicate extensions are detected so calling this routine multiple
  ** times with the same extension is harmless.
  **
  ** This routine stores a pointer to the extension in an array
  ** that is obtained from malloc().  If you run a memory leak
  ** checker on your program and it reports a leak because of this
  ** array, then invoke sqlite3_automatic_extension_reset() prior
  ** to shutdown to free the memory.
  **
  ** Automatic extensions apply across all threads.
  */
  int sqlite3_auto_extension(void *xEntryPoint);
  
  
  /*
  ****** EXPERIMENTAL - subject to change without notice **************
  **
  ** Disable all previously registered automatic extensions.  This
  ** routine undoes the effect of all prior sqlite3_automatic_extension()
  ** calls.
  **
  ** This call disabled automatic extensions in all threads.
  */
  void sqlite3_reset_auto_extension(void);
  
  
  /*
  ****** EXPERIMENTAL - subject to change without notice **************
  **
  ** The interface to the virtual-table mechanism is currently considered
  ** to be experimental.  The interface might change in incompatible ways.
  ** If this is a problem for you, do not use the interface at this time.
  **
  ** When the virtual-table mechanism stablizes, we will declare the
  ** interface fixed, support it indefinitely, and remove this comment.
  */
  
  /*
  ** Structures used by the virtual table interface
  */
  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,
                 int argc, const char *const*argv,
                 sqlite3_vtab **ppVTab, char**);
    int (*xConnect)(sqlite3*, void *pAux,
                 int argc, const char *const*argv,
                 sqlite3_vtab **ppVTab, char**);
    int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
    int (*xDisconnect)(sqlite3_vtab *pVTab);
    int (*xDestroy)(sqlite3_vtab *pVTab);
    int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
    int (*xClose)(sqlite3_vtab_cursor*);
    int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
                  int argc, sqlite3_value **argv);
    int (*xNext)(sqlite3_vtab_cursor*);
    int (*xEof)(sqlite3_vtab_cursor*);
    int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
    int (*xRowid)(sqlite3_vtab_cursor*, sqlite_int64 *pRowid);
    int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite_int64 *);
    int (*xBegin)(sqlite3_vtab *pVTab);
    int (*xSync)(sqlite3_vtab *pVTab);
    int (*xCommit)(sqlite3_vtab *pVTab);
    int (*xRollback)(sqlite3_vtab *pVTab);
    int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
                         void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                         void **ppArg);
  };
  
  /*
  ** 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
  ** form:
  **
  **         column OP expr
  **
  ** Where OP is =, <, <=, >, or >=.  The particular operator is stored
  ** in aConstraint[].op.  The index of the column is stored in 
  ** aConstraint[].iColumn.  aConstraint[].usable is TRUE if the
  ** expr on the right-hand side can be evaluated (and thus the constraint
  ** is usable) and false if it cannot.
  **
  ** The optimizer automatically inverts terms of the form "expr OP column"
  ** and makes other simplificatinos to the WHERE clause in an attempt to
  ** get as many WHERE clause terms into the form shown above as possible.
  ** The aConstraint[] array only reports WHERE clause terms in the correct
  ** form that refer to the particular virtual table being queried.
  **
  ** Information about the ORDER BY clause is stored in aOrderBy[].
  ** Each term of aOrderBy records a column of the ORDER BY clause.
  **
  ** The xBestIndex method must fill aConstraintUsage[] with information
  ** about what parameters to pass to xFilter.  If argvIndex>0 then
  ** the right-hand side of the corresponding aConstraint[] is evaluated
  ** and becomes the argvIndex-th entry in argv.  If aConstraintUsage[].omit
  ** is true, then the constraint is assumed to be fully handled by the
  ** virtual table and is not checked again by SQLite.
  **
  ** The idxNum and idxPtr values are recorded and passed into xFilter.
  ** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
  **
  ** The orderByConsumed means that output from xFilter will occur in
  ** the correct order to satisfy the ORDER BY clause so that no separate
  ** sorting step is required.
  **
  ** The estimatedCost value is an estimate of the cost of doing the
  ** particular lookup.  A full scan of a table with N entries should have
  ** a cost of N.  A binary search of a table of N entries should have a
  ** cost of approximately log(N).
  */
  struct sqlite3_index_info {
    /* Inputs */
    const int nConstraint;     /* Number of entries in aConstraint */
    const struct sqlite3_index_constraint {
       int iColumn;              /* Column on left-hand side of constraint */
       unsigned char op;         /* Constraint operator */
       unsigned char usable;     /* True if this constraint is usable */
       int iTermOffset;          /* Used internally - xBestIndex should ignore */
    } *const aConstraint;      /* Table of WHERE clause constraints */
    const int nOrderBy;        /* Number of terms in the ORDER BY clause */
    const struct sqlite3_index_orderby {
       int iColumn;              /* Column number */
       unsigned char desc;       /* True for DESC.  False for ASC. */
    } *const aOrderBy;         /* The ORDER BY clause */
  
    /* Outputs */
    struct sqlite3_index_constraint_usage {
      int argvIndex;           /* if >0, constraint is part of argv to xFilter */
      unsigned char omit;      /* Do not code a test for this constraint */
    } *const aConstraintUsage;
    int idxNum;                /* Number used to identify the index */
    char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
    int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
    int orderByConsumed;       /* True if output is already ordered */
    double estimatedCost;      /* Estimated cost of using this index */
  };
  #define SQLITE_INDEX_CONSTRAINT_EQ    2
  #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 */
  );
  
  /*
  ** Every module implementation uses a subclass of the following structure
  ** to describe a particular instance of the module.  Each subclass will
  ** be taylored 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
  ** string obtained from sqlite3_mprintf() to zErrMsg.  The method should
  ** take care that any prior string is freed by a call to sqlite3_free()
  ** prior to assigning a new string to zErrMsg.  After the error message
  ** is delivered up to the client application, the string will be automatically
  ** freed by sqlite3_free() and the zErrMsg field will be zeroed.  Note
  ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
  ** since virtual tables are commonly implemented in loadable extensions which
  ** do not have access to sqlite3MPrintf() or sqlite3Free().
  */
  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
  ** of the new function always causes an exception to be thrown.  So
  ** the new function is not good for anything by itself.  Its only
  ** purpose is to be a place-holder function that can be overloaded
  ** by virtual tables.
  **
  ** This API should be considered part of the virtual table interface,
  ** which is experimental and subject to change.
  */
  int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
  
  /*
  ** The interface to the virtual-table mechanism defined above (back up
  ** to a comment remarkably similar to this one) is currently considered
  ** to be experimental.  The interface might change in incompatible ways.
  ** If this is a problem for you, do not use the interface at this time.
  **
  ** When the virtual-table mechanism stablizes, we will declare the
  ** interface fixed, support it indefinitely, and remove this comment.
  **
  ****** EXPERIMENTAL - subject to change without notice **************
  */
  
  /*
  ** Undo the hack that converts floating point types to integer for
  ** builds on processors without floating point support.
  */
  #ifdef SQLITE_OMIT_FLOATING_POINT
  # undef double
  #endif
  
  #ifdef __cplusplus
  }  /* End of the 'extern "C"' block */
  #endif
  #endif
  