mysql 出发器增加第二个自增字段

DROP TRIGGER
IF EXISTS account;

delimiter $$


CREATE TRIGGER account BEFORE INSERT ON card_open FOR EACH ROW
BEGIN

SELECT
    max(account) INTO @my_auto_inc
FROM
    card_open ;

IF @my_auto_inc IS NULL THEN
 set @my_auto_inc=1000;
end if;



SET new.account = @my_auto_inc + 1 ;
END$$

delimiter ;