关于自身表外键触发器的实现_MySQL
bitsCN.com 关于自身表外键触发器的实现 目前遇到这样一个外键定义：`t_girl`.`tb1` CONSTRAINT `fk_1` FOREIGN KEY (`r_id`) REFERENCES `tb1` (`id`) ON DELETE CASCADE 目的是对于自己的另外一个字段进行约束， 其实这样看来， 后面的级联删除就没有必要了，因为针对的是同一张表的同一条记录。/* Trigger structure for table `tb1` */ DELIMITER $$ /*!50003 DROP TRIGGER*//*!50032 IF EXISTS */ /*!50003 `tr_tb1_before_insert` */$$ /*!50003 CREATE */ /*!50017 DEFINER = 'root'@'localhost' */ /*!50003 TRIGGER `tr_tb1_before_insert` BEFORE INSERT ON `tb1` FOR EACH ROW BEGIN set new.r_id = new.id; END */$$ DELIMITER ; 我们在除了INNODB之外的其他引擎可以直接用触发器来实现。 作者 yueliangdao0608 bitsCN.com
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