前言
数据库名称可以为【schoolDB】，字符集【utf8】，排序规则【utf8_general_ci】。
1、建表语句——DDL
CREATE TABLE `student` ( `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '学号', `createDate` datetime DEFAULT NULL COMMENT '创建时间', `userName` varchar(20) DEFAULT NULL COMMENT '用户名', `pwd` varchar(36) DEFAULT NULL COMMENT '密码', `phone` varchar(11) DEFAULT NULL COMMENT '手机号', `age` tinyint(3) unsigned DEFAULT NULL COMMENT '年龄', `sex` char(2) DEFAULT '男' COMMENT '性别', `introduce` varchar(255) DEFAULT NULL COMMENT '简介', PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
2、插入语句——DML
insert into student values(0,'2024-02-25 10:00:00','刘德华','123654', '15612345678',62,'男','永远的男神，爱你一万年，爱你经得起考研。'); insert into student values(0,'2024-02-25 10:00:00','刘青云','123154', '15612345678',65,'男','真正的演员，好角色用心演绎。'); insert into student values(0,'2024-02-25 10:00:00','周星驰','123624', '15612345678',61,'男','所有的电影都没有对爱情有过轻视。'); insert into student values(0,'2024-02-25 10:00:00','张翰','122654', '15612345678',32,'男','一起坐死在流星雨下。'); insert into student values(0,'2024-02-25 10:00:00','王祖贤','223654', '15612345678',27,'女','你再美你能比过王祖贤吗？'); insert into student (userName,age,introduce)values('刘亦菲',37,'神仙姐姐');
3、基础查询语句——DQL
# 1、基础查询 select * from student; # 2、分列匿名以及筛选数据查询 select userName as '姓名',age 年龄,sex '性别',introduce '简介' from student where pwd is not null; # 3、去重查询 select distinct sex '性别类型' from student; # 4、排序查询 select userName as '姓名',age 年龄,sex '性别',introduce '简介' from student ORDER BY age desc; # 5、分页查询·limit这是个重载函数， # 1个参数的limit用法是显示多少条信息 select * from student LIMIT 2; # 2个参数，参数1：从第N条开始查询，N的起始坐标为0条。参数2：查询条数 select * from student limit 4,2;
