mysql 触发器实现两个表的数据同步_MySQL
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mysql通过触发器实现两个表的同步
目前,在本地测试成功。
假设本地的两个数据库a和b,a下有表table1(id, val) b下有表table2(id, val)
假设希望当table1中数据更新,table2中数据同步更新。
代码:
DELIMITER $$
CREATE
/*[DEFINER = { user | CURRENT_USER }]*/
TRIGGER `a`.`触发器名` BEFORE UPDATE
ON `a`.`table1`
FOR EACH ROW BEGIN
IF new.id!=old.id THEN
UPDATE `b`.`table2` SET `b`.`table2`.id=new.id WHERE `b`.`table2`.val=old.val;
END IF;
END$$
DELIMITER ;
网上找了很多代码,在phpadmin中运行都不成功,总是语法错误,phpmyadmin也不能可视化建立触发器,所以找了另一个mysql管理工具,SQLyog。这个工具比较好,java写的,可以通过界面创建触发器,然后再把代码拷到phpmyadmin中运行,成功!bitsCN.com

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