my_ulonglong mysql_affected_rows(MYSQL *mysql)

Description

Returns the number of rows changed by the last UPDATE, deleted by the last DELETE or inserted by the last INSERT statement. May be called immediately after mysql_query() for UPDATE, DELETE, or INSERT statements. For SELECT statements, mysql_affected_rows() works like mysql_num_rows().

Return Values

An integer greater than zero indicates the number of rows affected or retrieved. Zero indicates that no records were updated for an UPDATE statement, no rows matched the WHERE clause in the query or that no query has yet been executed. -1 indicates that the query returned an error or that, for a SELECT query, mysql_affected_rows() was called prior to calling mysql_store_result(). Because mysql_affected_rows() returns an unsigned value, you can check for -1 by comparing the return value to (my_ulonglong)-1 (or to (my_ulonglong)~0, which is equivalent).

Errors

None.

Example

mysql_query(&mysql,"UPDATE products SET cost=cost*1.25 WHERE group=10");
printf("%ld products updated",(long) mysql_affected_rows(&mysql));

If you specify the flag CLIENT_FOUND_ROWS when connecting to mysqld, mysql_affected_rows() returns the number of rows matched by the WHERE statement for UPDATE statements.

Note that when you use a REPLACE command, mysql_affected_rows() returns 2 if the new row replaced an old row. This is because in this case one row was inserted after the duplicate was deleted.

If you use INSERT ... ON DUPLICATE KEY UPDATE to insert a row, mysql_affected_rows() returns 1 if the row is inserted as a new row and 2 if an existing row is updated.