今天学了SqlServer模糊查询、聚合函数 和分组查询

use Student

create table ClassInfo(
id int identity(1,1) primary key,
name varchar(20) not null

)

create table StudentInfo1(
id int identity(1,1) primary key,
name varchar(20) not null,
gender varchar(5) check(gender in('男','女')),
city varchar(10) default('郑州'),
physics int,
mathmatics int,
classId int foreign key references ClassInfo(id)

)

insert into ClassInfo values('一年一班')

insert into ClassInfo values('一年二班')

insert into ClassInfo values('二年一班')

insert into ClassInfo values('二年二班')

alter table StudentInfo1

add age int check(age>6 and age<130)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('张三',16,'男','开封',76,87,1)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('张四',17,'男','开封',66,85,1)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('刘三',19,'男','新乡',97,81,2)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('刘四',19,'女','新乡',86,87,2)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('刘五',16,'女','开封',76,87,2)

insert into StudentInfo1 (name,age,gender,city,physics,mathmatics,classId)

values ('刘实在',16,'男','许昌',76,87,2)

select * from StudentInfo1 where age>=19 and gender='男'

select * from StudentInfo1 where name like '[^刘%]'

select * from StudentInfo1 where name like '%实%'

select * from StudentInfo1 where name like '_实_'

select * from StudentInfo1 where age between 16 and 18

select * from StudentInfo1 where city in ('开封','许昌')

select SUM(physics) as '物理总成绩',SUM(mathmatics) as '数学总成绩',SUM(physics+mathmatics) as '总成绩' from StudentInfo1

select SUM(mathmatics) as '数学总成绩' from StudentInfo1

select SUM(physics+mathmatics) as '总成绩' from StudentInfo1

select MAX(physics) as '物理最高分' ,min(mathmatics) as '数学最低分' ,AVG(physics) as '物理平均分' from StudentInfo1

select COUNT(*) as '物理及格人数（成绩>80分）' from StudentInfo1 where physics >80

select city as '城市',COUNT(*)as '人数' from StudentInfo1 group by city

select city as '城市',MIN(age) as '最小年龄' from StudentInfo1 group by city
order by MIN(age) desc

select COUNT(*) as '人数',gender,classid from StudentInfo1 group by classId, gender

select MIN(age) as '最小年龄',city as '城市' from StudentInfo1 group by city

having COUNT(*)>=2

order by MIN(age) asc