更新前mysql触发器发生变化

Question

我需要在更新之前更改一列。这是我的触发器:

DELIMITER $$

CREATE TRIGGER select_for_update BEFORE UPDATE ON conductor
FOR EACH ROW
BEGIN
DECLARE first_frame1 varchar(255);
if NEW.video_id <> OLD.video_id THEN

select first_frame into first_frame1 from video where id_video=NEW.video_id;
SET NEW.first_frame=first_frame1;

END IF;
END$$

DELIMITER ;

但我收到此错误:

This version of MySQL doesn't yet support 'multiple triggers with the same action time and event for one table'

如何解决这个问题。

Answer 1

您已在该表上定义了触发器。请删除触发器，然后再次执行新的触发器。肯定不会报错。