mysql存储过程

CREATE DEFINER=`root`@`localhost` PROCEDURE `test`()
BEGIN
	DECLARE i int DEFAULT 0;
	DECLARE classSize int DEFAULT(0) ;
	SELECT count(0) INTO classSize FROM class;
	SELECT classSize;
	WHILE i < classSize DO
		UPDATE class set name = CONCAT('a',i) WHERE id in (select id FROM (SELECT id  FROM class LIMIT 1 OFFSET i) as temp);
		set i = i + 1;
	END WHILE;
END

批量修改class表里的name值