Mysql 双向关联触发器
时间：2021-07-01 10:21:17
帮助过：1人阅读
增加
delimiter //
create trigger InsertDemo
AFTER insert on vaccine.demo
for each row
Begin
if not exists (
select * from wechat.demo
where wechat.demo.id
= new.id)
then
INSERT INTO wechat.demo(wechat.demo.`name`,wechat.demo.`password`)
VALUES(new.name,new.password);
end if;
end;
//
delimiter ;
delimiter //
create trigger InsertDemo
AFTER insert on wechat.demo
for each row
Begin
if not exists (
select * from vaccine.demo
where vaccine.demo.id
= new.id)
then
INSERT INTO vaccine.demo(vaccine.demo.`name`,vaccine.demo.`password`)
VALUES(new.name,new.password);
end if;
end;
//
delimiter ;
//删除
CREATE TRIGGER de
After DELETE ON vaccine.demo
FOR EACH ROW
BEGIN
if exists (
select * from wechat.demo
where wechat.demo.id
= old.id)
then
DELETE FROM wechat.demo
WHERE wechat.demo.id
= OLD.id;
end if;
END;
CREATE TRIGGER de
After DELETE ON wechat.demo
FOR EACH ROW
BEGIN
if exists (
select * from vaccine.demo
where vaccine.demo.id
= old.id)
then
DELETE FROM vaccine.demo
WHERE vaccine.demo.id
= OLD.id;
end if;
END;
//修改
CREATE TRIGGER up
After UPDATE ON vaccine.demo
FOR EACH ROW
BEGIN
if not exists (
select * from wechat.demo
where wechat.demo.id
= old.id
and wechat.demo.`name`
=new.name
and wechat.demo.`password`
=new.password)
then
update wechat.demo
set wechat.demo.`name`
=new.name ,wechat.demo.`password`
=new.password
where wechat.demo.id
=old.id;
end if;
END;
CREATE TRIGGER up
After UPDATE ON wechat.demo
FOR EACH ROW
BEGIN
if not exists (
select * from vaccine.demo
where vaccine.demo.id
= new.id
and vaccine.demo.`name`
=new.name
and vaccine.demo.`password`
=new.password)
then
update vaccine.demo
set vaccine.demo.`name`
=new.name ,vaccine.demo.`password`
=new.password
where vaccine.demo.id
=old.id;
end if;
END;
Mysql 双向关联触发器
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