mysql 触发器语法与应用示例

//创建user表；
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
 `id` bigint(20) NOT NULL AUTO_INCREMENT,
 `account` varchar(255) DEFAULT NULL,
 `name` varchar(255) DEFAULT NULL,
 `address` varchar(255) DEFAULT NULL,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 
//创建对user表操作历史表
DROP TABLE IF EXISTS `user_history`;
CREATE TABLE `user_history` (
 `id` bigint(20) NOT NULL AUTO_INCREMENT,
 `user_id` bigint(20) NOT NULL,
 `operatetype` varchar(200) NOT NULL,
 `operatetime` datetime NOT NULL,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

DROP TRIGGER IF EXISTS `tri_insert_user`;
DELIMITER ;;
CREATE TRIGGER `tri_insert_user` AFTER INSERT ON `user` FOR EACH ROW begin
  INSERT INTO user_history(user_id, operatetype, operatetime) VALUES (new.id, 'add a user', now());
end
;;
DELIMITER ;

DROP TRIGGER IF EXISTS `tri_update_user`;
DELIMITER ;;
CREATE TRIGGER `tri_update_user` AFTER UPDATE ON `user` FOR EACH ROW begin
  INSERT INTO user_history(user_id,operatetype, operatetime) VALUES (new.id, 'update a user', now());
end
;;
DELIMITER ;

DROP TRIGGER IF EXISTS `tri_delete_user`;
DELIMITER ;;
CREATE TRIGGER `tri_delete_user` AFTER DELETE ON `user` FOR EACH ROW begin
  INSERT INTO user_history(user_id, operatetype, operatetime) VALUES (old.id, 'delete a user', now());
end
;;
DELIMITER ;