写一段创建mysql 数据库 user 表 的触发器代码
时间: 2023-06-07 12:09:34 浏览: 79
好的,以下是创建mysql数据库user表的触发器代码:
CREATE TRIGGER insert_user_trigger
BEFORE INSERT ON user
FOR EACH ROW
BEGIN
DECLARE msg varchar(255);
IF NEW.id IS NULL THEN
SET msg = CONCAT('Error: id column cannot be null!');
SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = msg;
END IF;
IF NEW.username IS NULL THEN
SET msg = CONCAT('Error: username column cannot be null!');
SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = msg;
END IF;
IF NEW.password IS NULL THEN
SET msg = CONCAT('Error: password column cannot be null!');
SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = msg;
END IF;
END;
请注意:这只是一个示例代码,具体实现可能会因表结构和需求而有所不同。