SQL/MySQL/Procedure Function/Lock

Get lock in a procedure

 
mysql>
mysql> delimiter $$
mysql>
mysql> CREATE PROCEDURE myProc()
    -> BEGIN
    ->     DECLARE lock_result INT;
    ->     IF get_lock("sp_critical_section_lock",60) THEN
    ->        /* This block can only be run by one user at a time*/
    ->        SELECT "got lock";
    ->        /* Critical code here */
    ->       SET lock_result=release_lock("sp_critical_section_lock");
    ->     ELSE
    ->        SELECT "failed to acquire lock";
    ->        /* Error handling here */
    ->     END IF;
    -> END$$
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> delimiter ;
mysql> call myProc();
+----------+
| got lock |
+----------+
| got lock |
+----------+
1 row in set (0.02 sec)
Query OK, 0 rows affected (0.02 sec)
mysql>
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>