目录
步骤:
1、创建学生表
2、插入数据
1)查询表中所有学生的信息
2)查询表中所有学生的姓名和英语成绩
3) 过滤表中的重复数据
4) 统计每个学生的总分
5) 所有学生总分上加上10
6) 使用别名表示学生分数
7)查询英语成绩大于90分的所有同学
8) 查询总分大于200分的所有同学
9)查询英语成绩在80到90之间的所有同学
10) 查询英语成绩不在80到90之间的所有同学
11)查询数学分数为89,90,91的同学
12)查询数学分数不为89,90,91的同学
13) 查询所有姓李的学生英语成绩
14) 查询数学分80且语文80分的同学
15)查询英语80或者总分200的同学
16)对学生数学成绩进行降序排序后输出
17)对总分从高到低的顺序输出
18)对姓李的学生按总成绩升序排序输出
19) 查询男生和女生分别有多少人,并将人数降序输出
20)查询男生和女生分别有多少人,并将人数降序输出,并查询出大于9的性别人数信息
命令:
create table student(
id int,
name varchar(20),
gender varchar(20),
chinese int,
math int,
english int
);
命令:
insert into student values
(1,'张明','男',89,78,90),
(2,'李进','男',67,53,95),
(3,'王五','女',87,78,77),
(4,'李一','女',88,98,92),
(5,'李财','男',82,84,67),
(6,'张宝','男',55,85,45),
(7,'黄蓉','女',75,65,30),
(7,'黄蓉','女',75,65,30);
命令:
select *from student;
命令:
select name,english from student;
命令:
select distinct *from student;
命令:
select name, chinese+math+english from student;
命令:
select name, chinese+math+english+10 from student;
命令:
select name, (chinese+math+english+10) sum_score from student;
命令:
select name,english from student where english>90;
命令:
select name,(chinese+math+english) sum_score from student where (chinese+math+english+10)>200;
命令:
select name,english from student where english between 80 and 90;
命令:
select name,english from student where english not between 80 and 90;
命令:
select name,math from student where math between 89 and 91;
或
select name,math from student where math=89 or math=90 or math=91;
命令:
select name,math from student where math not between 89 and 91;
命令:
select name,english from student where name like '李%';
命令:
select name from student where math=80 and chinese=80;
命令:
select name from student where english=80 or (math+english+chinese)=200;
命令:
select name,math from student order by math desc;
命令:
select *from student order by (math+english+chinese) desc;
命令:
select *from student where name like '李%' order by (math+english+chinese);
命令:
select gender, count(*) from student group by gender order by count(gender) desc;
命令:
elect gender, count(*) from student group by gender having count(gender)>9 order by count(gender) desc;