如何创建删除 php myadmin 的触发器 [英] How to create a trigger for delete php myadmin

问题描述

我有两个表 A 和 B.如果我删除表 A 中的条目，我想使用用户 ID 更新表 B 中条目的状态.我正在使用此代码:

I have two tables A and B. If I remove a entry in the table A, I want to update the status of the entry in the table B using the user id. I'm using this code:

CREATE TRIGGER blockuserundo BEFORE DELETE ON user_blocked
FOR EACH ROW BEGIN
UPDATE members SET ty_status = '1' WHERE user_id = OLD.block_user_id ;
END;

它显示如下错误:

触发器中没有新行删除

请指导我为上述场景编写查询.

Please guide me to write the query for the above scenario.

推荐答案

您需要将分隔符设置为 ;

You need to set the delimiter to something other then ;

DELIMITER |
CREATE TRIGGER blockuserundo BEFORE DELETE ON user_blocked
FOR EACH ROW BEGIN
UPDATE members SET ty_status = '1' WHERE user_id = OLD.block_user_id ;
END;
|
DELIMITER ;

以下代码按预期工作:

DROP TABLE IF EXISTS user_blocked;
CREATE TABLE user_blocked 
(
    block_user_id INT
);
DROP TABLE IF EXISTS members;
CREATE TABLE members 
(
    user_id INT,
    ty_status CHAR(1)
);

INSERT user_blocked
VALUES (1),(2),(3),(4),(5);

INSERT members
VALUES (1, '0'),(2, '0'),(3, '0'),(8, '0'),(9, '1');

DELIMITER |
CREATE TRIGGER blockuserundo BEFORE DELETE ON user_blocked
FOR EACH ROW BEGIN
UPDATE members SET ty_status = '1' WHERE user_id = OLD.block_user_id ;
END;
|
DELIMITER ;

SELECT * FROM members;

DELETE FROM user_blocked WHERE block_user_id IN(1,2);
SELECT * FROM members;

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