MySQL生成-单据号不重复

DELIMITER $$

CREATE

PROCEDURE `yunzhi`.`auto_no`(IN billType CHAR(2))

BEGIN
DECLARE v_timestr VARCHAR(8);
DECLARE v_cnt INT;
DECLARE rowcount BIGINT;

-- 当前日期（8位短日期）
SET v_timestr = DATE_FORMAT(NOW(), '%Y%m%d');
SELECT CONCAT(billType,v_timestr) INTO v_timestr;

SET autocommit = 0;
UPDATE no_seq SET sn = (sn + 1) WHERE timestr = v_timestr;

IF ROW_COUNT() = 0 THEN
INSERT INTO no_seq(timestr,sn) VALUE (v_timestr,1);
END IF;

SELECT CONCAT(v_timestr,LPAD(sn,7,0)) AS sn
FROM no_seq WHERE timestr = v_timestr;
COMMIT;
END$$

DELIMITER ;