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>
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