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SQLITE3_CHANGES(3)         Library Functions Manual         SQLITE3_CHANGES(3)

NAME
     sqlite3_changes, sqlite3_changes64 - count the number of rows modified

SYNOPSIS
     #include <sqlite3.h>

     int
     sqlite3_changes(sqlite3*);

     sqlite3_int64
     sqlite3_changes64(sqlite3*);

DESCRIPTION
     These functions return the number of rows modified, inserted or deleted
     by the most recently completed INSERT, UPDATE or DELETE statement on the
     database connection specified by the only parameter.  The two functions
     are identical except for the type of the return value and that if the
     number of rows modified by the most recent INSERT, UPDATE or DELETE is
     greater than the maximum value supported by type "int", then the return
     value of sqlite3_changes() is undefined.  Executing any other type of SQL
     statement does not modify the value returned by these functions.

     Only changes made directly by the INSERT, UPDATE or DELETE statement are
     considered - auxiliary changes caused by triggers, foreign key actions or
     REPLACE constraint resolution are not counted.

     Changes to a view that are intercepted by INSTEAD OF triggers are not
     counted.  The value returned by sqlite3_changes() immediately after an
     INSERT, UPDATE or DELETE statement run on a view is always zero.  Only
     changes made to real tables are counted.

     Things are more complicated if the sqlite3_changes() function is executed
     while a trigger program is running.  This may happen if the program uses
     the changes() SQL function, or if some other callback function invokes
     sqlite3_changes() directly.  Essentially:

     ⊕   Before entering a trigger program the value returned by
         sqlite3_changes() function is saved.  After the trigger program has
         finished, the original value is restored.

     ⊕   Within a trigger program each INSERT, UPDATE and DELETE statement
         sets the value returned by sqlite3_changes() upon completion as
         normal.  Of course, this value will not include any changes performed
         by sub-triggers, as the sqlite3_changes() value will be saved and
         restored after each sub-trigger has run.

     This means that if the changes() SQL function (or similar) is used by the
     first INSERT, UPDATE or DELETE statement within a trigger, it returns the
     value as set when the calling statement began executing.  If it is used
     by the second or subsequent such statement within a trigger program, the
     value returned reflects the number of rows modified by the previous
     INSERT, UPDATE or DELETE statement within the same trigger.

     If a separate thread makes changes on the same database connection while
     sqlite3_changes() is running then the value returned is unpredictable and
     not meaningful.

IMPLEMENTATION NOTES
     These declarations were extracted from the interface documentation at
     line 2599.

     SQLITE_API int sqlite3_changes(sqlite3*);
     SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);

SEE ALSO
     sqlite3_total_changes(3)

NetBSD 10.99                    August 24, 2023                   NetBSD 10.99