create database shujuku

use shujuku

use cangku

go

--注意事項：外鍵對本關系不一定是鍵

--2：創建外鍵時，鏈接表的主關鍵字已經確立

--3：當創建外部鍵后，外部鍵的取值必須來源于主鍵值

--4：要想刪除主鍵表時，必須先刪除外鍵表信息

?

?

create table student--學生表

(

sno varchar(50) not null primary key ,--學生主鍵

sname varchar(50)not null,

ssex varchar(50)not null,

sbirthdy date ,

class varchar(50)

)

select *from student

insert into student values('1','曾華','男','1987-09-01','95033')

insert into student values('2','李明','男','1985-10-01','95031')

insert into student values('3','王麗','女','1986-02-20','95033')

insert into student values('4','李軍','男','1986-01-23','95033')

insert into student values('5','王芳','女','1985-02-10','95031')

insert into student values('6','肖君','男','1991-06-03','95031')

drop table student

go

create table course--課程表

cno varchar(50)not null primary key,

cname varchar(50)not null,

tno varchar(50) references teacher(tno)not null, --教師外鍵

)

insert into course values('3-105','計算機','825')

insert into course values('3-245','操作系統','804')

insert into course values('6-166','數字電路','856')

insert into course values('9-888','高等數學','831')

select *from course

drop table course

go????????????????????????????? --cno課程編號? --sno學生編號--tno教師編號

create table score--成績表

(

sno varchar(50) references student(sno)not null, --學生外鍵

cno varchar(50) references course(cno)not null,??? --課程外鍵

degree decimal(4,1)

)

select *from score

insert into score values('1','3-245',86)

insert into score values('1','3-245',75)

insert into score values('2','3-245',68)

insert into score values('2','3-105',56)

insert into score values('3','3-105',76)

insert into score values('3','3-105',84)

insert into score values('4','3-105',85)

insert into score values('4','3-105',86)

insert into score values('5','3-105',87)

insert into score values('5','6-166',88)

insert into score values('6','6-166',89)

insert into score values('6','6-166',80)

drop table score

go

create table teacher--教師表

(

tno varchar(50) primary key not null,? --教師主鍵

tname varchar(50) not null,

tsex varchar(50)not null,

tbirthday date ,

prof varchar(50),

depart varchar(50)not null

)

insert into teacher values('804','李斌','男','1958-12-02','副教授','計算機系')

insert into teacher values('856','張旭','男','1969-03-12','講師','電子工程系')

insert into teacher values('825','王萍','女','1972-05-05','助教','計算機系')

insert into teacher values('831','劉冰','女','1977-08-14','助教','電子工程')

select *from teacher

drop table teacher

go

1、查詢Student表中的所有記錄的Sname、Ssex和Class列。

select sname,ssex,class from student

2、查詢教師所有的單位即不重復的Depart列。

select distinct depart from teacher

3、查詢Student表的所有記錄。

select*from student

4、查詢Score表中成績在到之間的所有記錄。

select*from score where DEGREE between 60 and 80

5、查詢Score表中成績為，或的記錄。

select*from? score where DEGREE in (85,86,88)

6、查詢Student表中“”班或性別為“女”的同學記錄。

select*from student where class='95031' and ssex='女'

7、以Class降序查詢Student表的所有記錄。

select*from student order by class desc

8、以Cno升序、Degree降序查詢Score表的所有記錄。

select*from score order by cno asc ,DEGREE desc

9、查詢“”班的學生人數。

select COUNT(*) from student where class='95031'

10、查詢Score表中的最高分的學生學號和課程號。（子查詢或者排序）

select sno,cno from score where degree=(select MAX(degree) from score)

select top 1* sno,cno from score order by degree desc????????????????? --為什么這樣做不行??????

11、查詢每門課的平均成績。

select avg(degree) from score where cno='3-245'

12、查詢Score表中至少有名學生選修的并以開頭的課程的平均分數。????? --重點題目

select cno,AVG(degree) degrees from score where cno like '3%' group by cno having COUNT(cno)>

13、查詢分數大于，小于的Sno列。

select sno from? score where DEGREE between 70 and 90

14、查詢所有學生的Sname、Cno和Degree列。

select sname ,cno,degree from student join score on student.sno=score.sno

15、查詢所有學生的Sno、Cname和Degree列。??????????????? --重點題目

select sno,cname,DEGREE from score join course on score.cno=course.cno

16、查詢所有學生的Sname、Cname和Degree列。

select sname,cname,DEGREE from student join score on student.sno=score.sno

join course on course.cno=score.cno

17、查詢“”班學生的平均分。

select avg(degree) from score where sno in (select sno from student where class='95033')

18、假設使用如下命令建立了一個grade表：??? --重點題目

create table grade

(

low? int not null,

upp? int not null,

[rank]? varchar (50)

)

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')

select? sno,cno,rank from score join grade on degree between low and upp order by rank? desc --表連接方法

select sno,cno,(select RANK from grade where score.degree between low and upp ) 級別 from score--子查詢

現查詢所有同學的Sno、Cno和rank列。

19、 查詢選修“-105”課程的成績高于“”號同學成績的所有同學的記錄。?? --重點題目

select * from score where cno='3-105' and DEGREE>(select degree from score where sno='2'and cno='3-105')

20、查詢score中選學多門課程的同學中分數為非最高分成績的記錄。--重點題目，看不懂

--select x.* from score x where degree<(select max(y.degree) from score y where? y.sno=x.sno)

select *from score where sno in (select sno from score group by sno

having COUNT (*)>1)

and degree not in (select MAX(degree)from score where sno in(select sno from? score group by sno having COUNT(sno)>1))

--查詢每門課最高分學生之外的其他學生分數信息

?select*from score a where DEGREE not in(select MAX(degree) from score b cno having a.cno=b.cno)

?select*from score a where DEGREE not in (select MAX(degree)from score b where a.cno=b.cno )

?--剔除選多門課的每門課最高分

?select*from score a where DEGREE not in (select MAX(degree)from score b where a.cno=b.cno ) and sno in

?(select cno from score group by cno having COUNT(*) >1)

21、查詢成績高于學號為“”、課程號為“-105”的成績的所有記錄。

select *from score where DEGREE>(select DEGREE from score where sno='2' and cno='3-105')

22、查詢和學號為的同學同年出生的所有學生的Sno、Sname和Sbirthday列。--重點題目

select sno,sname,sbirthdy from student where YEAR(sbirthdy)=(select YEAR(sbirthdy)from student where sno='3')

23、查詢“張旭“教師任課的學生成績。

select degree from score where cno in(select cno from course where tno=(select tno from? teacher where tname='張旭'))

24、查詢選修某課程的同學人數多于人的教師姓名。

select tname from teacher where tno in(select tno from course where cno =

(select cno from score group by cno having COUNT(cno)>5))

25、查詢班和班全體學生的記錄。 --重點題目

select *from student join score on student.sno=score.sno where class in('95033','95031')

26、 查詢存在有分以上成績的課程Cno.

select cno from score where DEGREE>85

27、查詢出“計算機系“教師所教課程的成績表。

select *from score where cno in(select cno from course where tno in(select tno from teacher where depart='計算機系'))

28、查詢“計算機系”與“電子工程系“不同職稱的教師的Tname和Prof

?select tname ,prof from teacher where prof not in( select prof from teacher group by prof having COUNT(prof)>1)

)

29、查詢選修編號為“-105“課程且成績至少高于選修編號為“-245”的同學的Cno、Sno和Degree,并按Degree從高到低次序排序。

select*from score where cno='3-105'? and degree>(select MAX(degree) from score where cno='3-245') order by DEGREE asc

30、查詢選修編號為“-105”且成績高于選修編號為“-245”課程的同學的Cno、Sno和Degree.

select*from score where cno='3-105'and DEGREE>(select MAX(degree)from score where cno='3-245')

31、查詢所有教師和同學的name、sex和birthday.

select sname ,ssex,sbirthdy from student

union

select tname,tsex,tbirthday from teacher

32、查詢所有“女”教師和“女”同學的name、sex和birthday.

select sname,ssex,sbirthdy from student where ssex='女'

union

select tname,tsex,tbirthday from teacher where tsex='女'

33、查詢成績比該課程平均成績低的同學的成績表。

select *from score where degree <(select AVG(degree)from score )

34、查詢所有任課教師的Tname和Depart.

select tname from teacher where tno in (select tno from course where cno? in (select cno from score))??????????????????????????????????

35 、查詢所有未講課的教師的Tname和Depart.

select tname from teacher where tno not in(select tno from course where cno in (select cno from score ))

36、查詢至少有名男生的班號。

select class from student group by class having COUNT(class)>=2

37、查詢Student表中不姓“王”的同學記錄。

select*from student where sname not like '王%'

38、查詢Student表中每個學生的姓名和年齡。

select sname,DATEDIFF(YEAR,sbirthdy,getdate()) age from student

39、查詢Student表中最大和最小的Sbirthday日期值。

select MAX(sbirthdy),MIN(sbirthdy)from student

40、以班號和年齡從大到小的順序查詢Student表中的全部記錄。

select*from student order by class desc,sbirthdy asc

41、查詢“男”教師及其所上的課程。

select tname ,cname from teacher join course on teacher.tno=course.tno? where tsex='男'

42、查詢最高分同學的Sno、Cno和Degree列。

select*from score where DEGREE in(select MAX(degree)from score)

43、查詢和“李軍”同性別的所有同學的Sname.

select sname from student where ssex in? (select ssex from student where sname='李軍')

44、查詢和“李軍”同性別并同班的同學Sname.

select sname from student where ssex in (select ssex from student where sname='李軍')and

?class in(select class from student where sname='李軍')

45、查詢所有選修“計算機導論”課程的“男”同學的成績表。

select *from score where sno in(select sno from student where ssex='男')

?and cno in (select cno from course where cname='計算機')

?

轉載于:https://www.cnblogs.com/275147378abc/p/4451754.html

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