Mysql存储过程快速生成0000-9999号码

DELIMITER $$
DROP PROCEDURE IF EXISTS sp_test1$$
CREATE PROCEDURE sp_test1()


BEGIN
DECLARE i INT;
DECLARE size INT DEFAULT 0;
DECLARE str VARCHAR(3) DEFAULT '';
DECLARE num VARCHAR(4) DEFAULT '';
SET i=0;
SET autocommit=0;
WHILE i<10000 DO
 SET size = LENGTH(''+i);
  IF size=1 THEN
     SET str = '000';
  ELSEIF size=2 THEN
     SET str='00';
  ELSEIF size=3 THEN
     SET str='0';
  ELSE 
     SET str='';
  END IF;
  SET num=CONCAT(str,i);
  INSERT INTO temp(number) VALUES(num);
 SET i=i+1;

END WHILE;

COMMIT;

    END$$


DELIMITER ;