MySQL用触发器同步两张表

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在MySQL环境下面，建立相关触发器，在两个表之间相关sql，希望能帮到大家

1.建person表

CREATE TABLE `person` (  `id` int(11) DEFAULT NULL,  `name` varchar(256) DEFAULT NULL,  `sex` char(16) DEFAULT NULL)

建person_ex

CREATE TABLE `person_ex` (  `id` int(11) DEFAULT NULL,  `name` varchar(256) DEFAULT NULL,  `sex` char(16) DEFAULT NULL)

2.实现的目标当person新增一条记录，更新一条记录或者删除一条记录，person_ex中sex字段为M的记录跟着改变

sql代码如下：

创建插入触发器

create trigger person_trigger AFTER insert on person  for each row begin set @x = "hello trigger";IF new.sex = 'M'THEN       INSERT INTO person_ex(id,name,sex) VALUES (New.id,new.`name`,new.sex);END IF;end;

创建更新触发器：

create trigger person_trigger_update AFTER UPDATE on person  for each row begin set @x = "trigger UPDATE";IF new.sex = 'M'THENDELETE from person_ex where person_ex.id = new.id;       INSERT into person_ex SELECT * from person where person.id = new.id;END IF;end;

创建删除触发器：

create trigger person_trigger_delete AFTER DELETE on person  for each row begin set @x = "trigger DELETE";       DELETE FROM person_ex where person_ex.id = old.id;end;

3.测试SQL代码：

INSERT into person (id,name,sex) VALUES (1,'chigo','M')

INSERT into person (id,name,sex) VALUES (2,'Tony','F')

update person set name = 'vara' , sex = 'F' where id = 1

update person set name = 'Tony' , sex = 'M' where id = 1

update person set name = 'vara' , sex = 'M' where id = 1

DELETE from person where id = 1INSERT into person_ex SELECT * from person where person.id = 1update person set name = 'vara' , sex = 'F' where id = 1

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