做了一下 以前学的大多数没有忘记

拿来练手正好，我新手，谢谢楼主啦

create table Student
(
Sno varchar(10) not null primary key,
Sname varchar(10) not null,
Ssex varchar(1) not null,
Sbirthday datetime not null,
Sage int not null,
Sdept varchar(20)
)
go
create table Coures
(
Cno int not null primary key,
Cname varchar(20) not null,
Cpno varchar(20) not null,
Ccredit int
)
go
create table SC
(
Sno int not null primary key,
Cno int not null,
Grade int
)
go

--1.
select Sno,Sname from Student

--2.
select Sname,Sno,Sdept from Student

--3.
select * from Student

--4.
select Sname,Sbirthday from Student

--5.
select Sname,Sbirthday,Sdept from Student where Sdept>='a' and Sdept<='z'

--6.
select Sname as 姓名,Sbirthday as 出生日期,Sdept as 系课 from Student

--7.
select distinct Sno from SC where Cno is not null

--8.
select Sname from Student where Sdept='计算机'

--9.
select Sname,Sage from Student where Sage<20 --方法1
select Sname,Sage from Student where not Sage>=20 --方法2

--10.
select distinct Sno from SC where Grade>=60

--11.
select Sname,Sdept,Sage from Student where Sage>=20 and Sage<=30

--12.
select Sname,Sdept,Sage from Student where Sage<20 or Sage>30

--13.
select Sname,Ssex from Student where Sno in('信息','数学','计算机')

--14.
select Sname,Ssex from Student where Sno not in('信息','数学','计算机')

--15.
select * from Student where Sno like '95001%' --方法1
select * from Student where Sno like '[9][5][0][0][1]%' --方法2

--16.
select Sname,Sno,Ssex from Student where Sname like '刘'

--17.
select Sname from Student where Sname like '欧阳_'

--18.
select Sname,Sno from Student where Sname like '_阳_'

--19.
select Sname from Student where Sname not like '刘%'

--20.
select Cno,Ccredit from Coures where Cname like 'C'

--21.
select Cno,Ccredit from Coures where Cname like 'H%T__'

--22.
select Sno,Cno from SC where Grade is null and Cno is not null

--23.
select Sno,Cno from SC where Grade is null

--24.
select Sname from Student where Sdept='计算机' and Sage<20

--25.
select Sname,Ssex from Student where Sdept='计算机' or Sdept='数学' or Sdept='信息'

--26.
select Sno,Grade from SC where Cno=3 order by Grade Desc

--27.题目好像有问题,在创建的三个表中没有找到系号

--28.
select count(*) from Student

--29.
select count(Cno) from SC where Sno is not null

--30.
select avg(Grade) as 平均成绩 from SC where Cno=1

很全的题目啊，，

用空拿来练习练习，刚入门，正需要这些东东！谢谢！

那位老大弄点实例数据呗，好像这样更容易理解！

初学者，谢谢分享

看来还要努力学习啊