SQL Server 练习

use master

if exists(select * from sys.databases where name='db_Test')
    drop database db_Test
go

create database db_Test
go

use db_Test
go

if exists(select * from sys.objects where name='Student')
    drop table Student
    go
create table Student--学生表
(
    Sno nvarchar(200) primary key,--学号
    Sname nvarchar(200) not null,--姓名
    Ssex nvarchar(200) not null,--性别
    Sbirthday datetime,--生日
    Class nvarchar(200)--班级
)
go

if exists(select * from sys.objects where name='Course')
    drop table Course
    go
create table Course--课程表
(
    Cno nvarchar(200) primary key,--课程号
    Cname nvarchar(200) not null,--课程名
    Tno nvarchar(200) not null--教工编号
)
go

if exists(select * from sys.objects where name='Score')
    drop table Score
    go
create table Score--成绩表
(
    Sno nvarchar(200) not null,--学号
    Cno nvarchar(200) not null,--课程号
    Degree decimal(4,1)--成绩
)
go

if exists(select * from sys.objects where name='Teacher')
    drop table Teacher
    go
create table Teacher--教师表
(
    Tno nvarchar(200) primary key,--教工编号
    Tname nvarchar(200) not null,--教工姓名
    Tsex nvarchar(200) not null,--教工性别
    Tbirthday datetime,--教工出生年月
    Prof nvarchar(200),--职称
    Ddpart nvarchar(200) not null--教工所在部门
)

insert into Student values('','曾华','男','1997-09-01','')
insert into Student values('','匡华','男','1975-10-12','')
insert into Student values('','王丽','女','1976-10-23','')
insert into Student values('','李军','男','1974-10-12','')
insert into Student values('','王芳','女','1973-10-12','')
insert into Student values('','陆君','男','1972-10-12','')

insert into Course values('3-105','计算机导论','')
insert into Course values('3-245','操作系统','')
insert into Course values('6-166','数字电路','')
insert into Course values('9-888','高等数学','')

insert into Score values('','3-245',86)
insert into Score values('','3-245',75)
insert into Score values('','3-245',90)
insert into Score values('','3-105',77)
insert into Score values('','3-105',88)
insert into Score values('','9-888',72)
insert into Score values('','3-245',66)
insert into Score values('','3-245',71)
insert into Score values('','9-888',89)
insert into Score values('','3-245',96)

insert into Teacher values('','李成','男','1958-12-20','副教授','计算机系')
insert into Teacher values('','李三','男','1958-11-20','副教授','电子工程系')
insert into Teacher values('','赵四','女','1958-09-20','副教授','计算机系')
insert into Teacher values('','鼠标','男','1958-07-20','副教授','电子工程系')

select * from Student
select * from Teacher
select * from Score
select * from Course

select [Sno] 学号, [Sname] 姓名, [Ssex] 性别, [Sbirthday] 生日, [Class] 班级 from Student --学生表
select [Tno] 教工编号, [Tname] 教工姓名, [Tsex] 教工性别, [Tbirthday] 教工生日, [Prof] 职称, [Ddpart] 教师所在部门 from Teacher --教师表
select [Sno] 学号, [Cno] 课程号, [Degree] 成绩 from Score --分数表
select [Cno] 课程号, [Cname] 课程名, [Tno] 教工编号 from Course --课程表

--1、 查询Student表中的所有记录的Sname、Ssex和Class列。
select Sname,Ssex,Class from Student

--2、 查询教师所有的单位即不重复的Depart列。
select distinct Ddpart from Teacher

--3、 查询Student表的所有记录。
select * from Student

--4、 查询Score表中成绩在60到80之间的所有记录。
select * from Score where Degree between 60 and 80

--5、 查询Score表中成绩为85，86或88的记录。
select * from Score where Degree in(85,86,88)

--6、 查询Student表中“95031”班或性别为“女”的同学记录。
select * from Student where Class='' or Ssex='女'

--7、 以Class降序查询Student表的所有记录。
select * from Student order by Class desc

--8、 以Cno升序、Degree降序查询Score表的所有记录。
select * from Score order by Cno asc,Degree desc

--9、 查询“95031”班的学生人数。
select count(*) as 人数 from Student where Class=''

--10、 查询Score表中的最高分的学生学号和课程号。（子查询或者排序）
select top 1 Sno,Cno from Score order by Degree desc    --排序
select sno,cno from score where degree=(select MAX(degree) from score)--子查询

--11、查询每门课的平均成绩。
select cno,AVG(degree) 平均成绩 from score group by cno
--select A.Cname 科目,AVG(B.Degree) as 平均成绩 from Course A inner join Score B on A.Cno=B.Cno group by Cname    --第二种

--12、查询Score表中至少有5名学生选修的并以3开头的课程的平均分数。
select AVG(Degree) as 平均分数 from Score  where Cno like '3%' group by Cno having count(cno)>5
--select AVG(degree) as 平均分数 from score where cno=(select cno from score where cno like '3%' group by cno having COUNT(cno)>5)    --第二种

--13、查询分数大于70，小于90的Sno列。
select sno from score where DEGREE>70 and DEGREE<90

--14、查询所有学生的Sname、Cno和Degree列。
select A.Sname,B.Cno,B.Degree from Student A inner join Score B on A.Sno=B.Sno
--select A.sname,B.cno,B.degree from student A,score B where A.sno=B.sno    --第二种

--15、查询所有学生的Sno、Cname和Degree列。
select A.Sno,C.Cname,B.Degree from Student A inner join Score B on A.Sno=B.Sno inner join Course C on B.Cno=C.Cno
--select A.sno,B.cname,A.degree from score A,course B where A.cno=B.cno    --第二种

--16、查询所有学生的Sname、Cname和Degree列。
select A.Sname,C.Cname,B.Degree from Student A inner join Score B on A.Sno=B.sno inner join Course C on B.Cno=C.Cno

--17、 查询“95033”班学生的平均分。
select AVG(Degree) 平均分 from Score A inner join Student B on A.Sno=B.Sno where B.Class=''
--select AVG(sc.Degree) 平均分 from student st,Score sc where st.Class='95033' and st.Sno=sc.Sno

--18、假设使用如下命令建立了一个grade表：
--create table grade(low int,upp int,rank nvarchar(200))
--insert into grade values(90,100,'A')
--insert into grade values(80,89,'B')
--insert into grade values(70,79,'C')
--insert into grade values(60,69,'D')
--insert into grade values(0,59,'E')
--现查询所有同学的Sno、Cno和rank列。
select B.Sno,B.Cno,C.rank from Student A,Score B,grade C where A.Sno=B.Sno and B.Degree between C.low and C.upp
--select st.Sno,sc.Cno,gr.rank from student st,Score sc,grade gr where st.Sno=sc.Sno and sc.Degree>=gr.low and sc.Degree<=gr.upp

--19、查询选修“3-105”课程的成绩高于“109”号同学成绩的所有同学的记录。
select * from Score A inner join Student B on A.Sno=B.Sno where A.Degree in (select Degree from Score where Cno='3-105' and Degree>(select Degree from Score where Sno=109))
--select st.*,sc.Cno,sc.Degree from student st,Score sc where sc.Cno='3-105' and sc.DEGREE>(select degree from Score where Sno='109')and sc.Sno=st.Sno

--20、查询score中选学多门课程的同学中分数为非最高分成绩的记录。
--select Sno from Score group by Sno having count(Sno)>1--选修多门课的学号
--select MAX(Degree) from Score where Sno in(select Sno from Score group by Sno having count(Sno)>1)    --选修多门课学生中成绩最高的分数
select * from Score where Sno in(select sno from Score group by Sno having COUNT(*)>1) and  Degree<(select MAX(degree) from Score where Sno in(select sno from Score group by Sno having count(*)>1))

--21、查询成绩高于学号为“109”、课程号为“3-105”的成绩的所有记录。
select * from Score where Cno='3-105' and Degree >(select Degree from Score where Sno=''and Cno='3-105') 

--22、查询和学号为108的同学同年出生的所有学生的Sno、Sname和Sbirthday列。
select Sno,Sname,Sbirthday from Student where Sbirthday=(select Sbirthday from Student where Sno=108)
--select sno,sname,sbirthday from student where year(Sbirthday)=(select year(Sbirthday) from student where Sno='108')

--23、查询“赵四“教师任课的学生成绩。
select * from Score where Cno=(select Cno from Course where Tno=(select Tno from Teacher where Tname='赵四'))

--24、查询选修某课程的同学人数多于5人的教师姓名。
select tname from Teacher where Tno in(select tno from Course where Cno in(select cno from Score group by Cno having COUNT(cno)>5))

--25、查询95033班和95031班全体学生的记录。
select * from Student where Class in(95033,95031)
--select * from student where class='95033' or class='95031'

--26、查询存在有85分以上成绩的课程Cno.
select distinct Cno from Score where Degree>85

--27、查询出“计算机系“教师所教课程的成绩表。
select * from Score where Cno in(select Cno from Course where Tno in(select Tno from Teacher where Ddpart='计算机系'))

--28、查询“计算机系”与“电子工程系“不同职称的教师的Tname和Prof。
select tname,prof from Teacher where Prof not in(select Prof from Teacher where Ddpart='计算机系'and Prof in(select Prof from Teacher where Ddpart='电子工程系'))

--29、查询选修编号为“3-105“课程且成绩至少高于选修编号为“3-245”的同学的Cno、Sno和Degree,并按Degree从高到低次序排序。
select * from Score where Cno='3-105' and Degree>(select top 1 Degree from Score where Cno='3-245' order by Degree asc) order by Degree desc
--select cno,sno,degree from Score where Cno='3-105' and DEGREE>any(select DEGREE from Score where Cno='3-245') order by Degree desc    --第二种

--30、查询选修编号为“3-105”且成绩高于选修编号为“3-245”课程的同学的Cno、Sno和Degree.
select cno,sno,DEGREE from Score where Cno='3-105' and degree>any(select DEGREE from Score where Cno='3-245')

--31、 查询所有教师和同学的name、sex和birthday.
select sname,ssex,sbirthday from Student,teacher

--32、查询所有“女”教师和“女”同学的name、sex和birthday.
select sname name,ssex sex,sbirthday birthday from student where Ssex='女' union select tname,tsex,tbirthday from Teacher where Tsex='女'

--33、 查询成绩比该课程平均成绩低的同学的成绩表。
select * from Score a where Degree<(select AVG(Degree) from Score b where a.Cno=b.Cno)
--select * from Score where Degree<(select AVG(A.Degree) as 平均分 from Score A inner join Course B on A.Cno=B.Cno)            --第二种
--select AVG(A.Degree) as 平均分 from Score A inner join Course B on A.Cno=B.Cno                                            --查询每一科平均成绩

--34、查询所有任课教师的Tname和Ddpart.
select tname,Ddpart from Teacher,Course where Teacher.Tno=Course.Tno

--35、查询所有未讲课的教师的Tname和Ddpart.
select tname,Ddpart from Teacher where Tno not in(select teacher.Tno from Teacher,Course where Teacher.Tno=Course.Tno)

--36、查询至少有2名男生的班号。
select Class from Student where Ssex='男' group by Class having count(Class)>=2

--37、查询Student表中不姓“王”的同学记录。
select * from Student where Sname not like '王%'

--38、查询Student表中每个学生的姓名和年龄。
select Sname,YEAR(GETDATE())-YEAR(Sbirthday) age from Student

--39、查询Student表中最大和最小的Sbirthday日期值。
select max(Sbirthday) 最大值,min(Sbirthday) 最小值 from Student
--select convert(date,MAX(sbirthday)),convert(date,MIN(sbirthday)) from student    --第二种

--40、以班号和年龄从大到小的顺序查询Student表中的全部记录。
select * from Student order by Class desc,Year(GETDATE())-YEAR(Sbirthday) desc
--select * from student order by Class desc ,Sbirthday asc    --第二种

--41、查询“男”教师及其所上的课程。
select A.Tname,B.Cname from Teacher A inner join Course B on A.Tno=B.Tno where A.Tsex='男'
--select t.Tname,c.Cname from Teacher t,Course c where Tsex='男' and t.Tno=c.Tno    --第二种

--42、查询最高分同学的Sno、Cno和Degree列。
select A.Sno,B.Cno,B.Degree from Student A inner join Score B on A.Sno=B.Sno where A.Sno=(select top 1 Sno from Score order by Degree desc)
--select * from Score where degree=(select MAX(DEGREE) from Score)    --第二种

--43、查询和“李军”同性别的所有同学的Sname.
select Sname from Student where Ssex=(select Ssex from Student where Sname='李军')

--44、查询和“匡华”同性别并同班的同学Sname.
select Sname from Student where Ssex=(select Ssex from Student where Sname='匡华') and Class=(select Class from Student where Sname='匡华')

--45、查询所有选修“计算机导论”课程的“男”同学的成绩表。
select * from Score where Cno=(select Cno from Course where Cname='计算机导论') and Sno in(select Sno from Student where Ssex='男')
--select Score.* from Score,student where Cno=(select Cno from Course where Cname='计算机导论') and student.Ssex='男' and student.Sno=Score.Sno    --第二种方法