DDL

​
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;​

DML

​
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);​

打开student表后，新建查询

create view student_age_big20 as
SELECT * FROM `student` where age>20
#复杂化sql即可
;

就会创建视图成功