6.4.18 mysql_stmt_next_result()

int
mysql_stmt_next_result(MYSQL_STMT *mysql)

Description

This function is used when you use prepared CALL statements to execute stored procedures, which can return multiple result sets. Use a loop that calls mysql_stmt_next_result() to determine whether there are more results. If a procedure has OUT or INOUT parameters, their values will be returned as a single-row result set following any other result sets. The values will appear in the order in which they are declared in the procedure parameter list.

For information about the effect of unhandled conditions on procedure parameters, see Condition Handling and OUT or INOUT Parameters.

mysql_stmt_next_result() returns a status to indicate whether more results exist. If mysql_stmt_next_result() returns an error, there are no more results.

Before each call to mysql_stmt_next_result(), you must call mysql_stmt_free_result() for the current result if it produced a result set (rather than just a result status).

After calling mysql_stmt_next_result() the state of the connection is as if you had called mysql_stmt_execute(). This means that you can call mysql_stmt_bind_result(), mysql_stmt_affected_rows(), and so forth.

It is also possible to test whether there are more results by calling mysql_more_results(). However, this function does not change the connection state, so if it returns true, you must still call mysql_stmt_next_result() to advance to the next result.

For an example that shows how to use mysql_stmt_next_result(), see Section 3.6.5, “Prepared CALL Statement Support”.

Return Values

Return Value	Description
0	Successful and there are more results
-1	Successful and there are no more results
>0	An error occurred

Errors

• CR_COMMANDS_OUT_OF_SYNC

  Commands were executed in an improper order.

• CR_SERVER_GONE_ERROR

  The MySQL server has gone away.

• CR_SERVER_LOST

  The connection to the server was lost during the query.

• CR_UNKNOWN_ERROR

  An unknown error occurred.