MySQL的触发器创建与使用——使用Baidu Comate生成与触发测试完整过程

CREATE TABLE `student` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '学号',
  `createDate` datetime DEFAULT NULL,
  `userName` varchar(20) DEFAULT NULL,
  `pwd` varchar(36) DEFAULT NULL,
  `phone` varchar(11) DEFAULT NULL,
  `age` tinyint(3) unsigned DEFAULT NULL,
  `sex` char(2) DEFAULT '男',
  `introduce` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
 
CREATE TABLE `result` (
  `rid` int(11) NOT NULL AUTO_INCREMENT COMMENT '成绩编号',
  `testName` varchar(255) DEFAULT NULL COMMENT '测试名称',
  `score` double(4,2) DEFAULT NULL COMMENT '成绩',
  `studentId` int(11) DEFAULT NULL COMMENT '学生id',
  PRIMARY KEY (`rid`),
  KEY `studentId` (`studentId`),
  CONSTRAINT `result_ibfk_1` FOREIGN KEY (`studentId`) REFERENCES `student` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
insert into student values(0,'2024-02-25 10:10:10','赵灵儿','123',
'15612345678',16,'女','逍遥哥哥，你终于找到我了。');
insert into student values(0,'2024-02-25 10:10:10','王语嫣','123',
'15612345678',17,'女','慕容复，我和你不共戴天。');
insert into student values(0,'2024-02-25 10:10:10','龙姑娘','123',
'15612345678',22,'女','我想过过过儿过过的日子。');
insert into student values(0,'2024-02-25 10:10:10','杨过','123',
'15612345678',18,'男','一遇杨过误终身。');
insert into student values(0,'2024-02-25 10:10:10','杨逍','123',
'15612345678',27,'男','杨过跟程英的大儿子。');
insert into student (userName,age,introduce)values('黄衣女子',26,'杨过与龙姑娘的大女儿。');
 
insert into result values(0,'政治',96,1);
insert into result values(0,'地理',86,5);
insert into result values(0,'政治',77,3);
insert into result values(0,'英语',99,3);
insert into result values(0,'历史',22,6);
insert into result values(0,'化学',69,2);
insert into result values(0,'Java',79,5);
insert into result values(0,'Java',67,6);
insert into result values(0,'政治',97,2);
insert into result values(0,'物理',76,6);
insert into result values(0,'物理',82,2);
insert into result values(0,'化学',56,4);

DELIMITER //

CREATE TRIGGER tr_before_insert_student
BEFORE INSERT ON student
FOR EACH ROW
BEGIN
    IF NEW.userName IN ('张', '王', '李', '赵') THEN
        SIGNAL SQLSTATE '45000'
        SET MESSAGE_TEXT = '不允许添加姓名为张、王、李、赵的用户';
    END IF;
END;

//

DELIMITER ;

DELIMITER //

CREATE TRIGGER tr_before_insert_student
BEFORE INSERT ON student
FOR EACH ROW
BEGIN
    IF NEW.userName LIKE '张%' OR NEW.userName LIKE '王%' OR NEW.userName LIKE '李%' OR NEW.userName LIKE '赵%' THEN
        SIGNAL SQLSTATE '45000'
        SET MESSAGE_TEXT = '不允许添加姓名以张、王、李、赵开头的用户';
    END IF;
END;

//

DELIMITER ;

INSERT INTO `student` (`createDate`, `userName`,  `phone`, `age`, `sex`, `introduce`)
VALUES (
    NOW(), -- 当前日期和时间
    '王晓易',
    CONCAT('1', FLOOR(RAND() * (999999999 - 100000000 + 1)) + 100000000), -- 随机生成11位手机号（以1开头）
    FLOOR(RAND() * (50 - 16 + 1)) + 16, -- 随机生成16到50之间的年龄
    IF(RAND() > 0.5, '男', '女'), -- 随机分配性别
    CONCAT('这是', '王晓易', '的介绍。') -- 简单的介绍文本（可选，仅作示例）
);