一、設有一數據庫，包括四個表：學生表（Student）、課程表（Course）、成績表（Score）以及教師信息表（Teacher）。四個表的結構分別如表1-1的表（一）~表（四）所示，數據如表1-2的表（一）~表（四）所示。用SQL語句創建四個表并完成相關題目。

???????????????? 表1-1數據庫的表結構

表（一）Student (學生表)?

屬性名	數據類型	可否為空	含 義
Sno	varchar (20)	否	學號（主碼）
Sname	varchar (20)	否	學生姓名
Ssex	varchar (20)	否	學生性別
Sbirthday	datetime	可	學生出生年月
Class	varchar (20)	可	學生所在班級

?

表（二）Course（課程表）

屬性名	數據類型	可否為空	含 義
Cno	varchar (20)	否	課程號（主碼）
Cname	varchar (20)	否	課程名稱
Tno	varchar (20)	否	教工編號（外碼）

表（三）Score(成績表)

屬性名	數據類型	可否為空	含 義
Sno	varchar (20)	否	學號（外碼）
Cno	varchar (20)	否	課程號（外碼）
Degree	Decimal(4,1)	可	成績
主碼：Sno+ Cno

表（四）Teacher(教師表)

屬性名	數據類型	可否為空	含 義
Tno	varchar (20)	否	教工編號（主碼）
Tname	varchar (20)	否	教工姓名
Tsex	varchar (20)	否	教工性別
Tbirthday	datetime	可	教工出生年月
Prof	varchar (20)	可	職稱
Depart	varchar (20)	否	教工所在部門

表1-2數據庫中的數據

表（一）Student

Sno	Sname	Ssex	Sbirthday	class
108	曾華	男	1977-09-01	95033
105	匡明	男	1975-10-02	95031
107	王麗	女	1976-01-23	95033
101	李軍	男	1976-02-20	95033
109	王芳	女	1975-02-10	95031
103	陸君	男	1974-06-03	95031

?

表（二）Course

Cno	Cname	Tno
3-105	計算機導論	825
3-245	操作系統	804
6-166	數字電路	856
9-888	高等數學	831

表（三）Score

Sno	Cno	Degree
103	3-245	86
105	3-245	75
109	3-245	68
103	3-105	92
105	3-105	88
109	3-105	76
101	3-105	64
107	3-105	91
108	3-105	78
101	6-166	85
107	6-166	79
108	6-166	81

表（四）Teacher

Tno	Tname	Tsex	Tbirthday	Prof	Depart
804	李誠	男	1958-12-02	副教授	計算機系
856	張旭	男	1969-03-12	講師	電子工程系
825	王萍	女	1972-05-05	助教	計算機系
831	劉冰	女	1977-08-14	助教	電子工程系

?

#建學生信息表student
create table student
(
sno varchar(20) not null primary key,
sname varchar(20) not null,
ssex varchar(20) not null,
sbirthday datetime,
class varchar(20));
#建立教師表
create table teacher
(
tno varchar(20) not null primary key,
tname varchar(20) not null,
tsex varchar(20) not null,
tbirthday datetime,
prof varchar(20),
depart varchar(20) not null);
#建立課程表course
create table course
(
cno varchar(20) not null primary key,
cname varchar(20) not null,
tno varchar(20) not null,
foreign key(tno) references teacher(tno));
#建立成績表
create table score
(
sno varchar(20) not null primary key,
foreign key(sno) references student(sno),
cno varchar(20) not null,
foreign key(cno) references course(cno),
degree decimal);#添加學生信息
insert into student values('108','曾華','男','1977-09-01','95033');
insert into student values('105','匡明','男','1975-10-02','95031');
insert into student values('107','王麗','女','1976-01-23','95033');
insert into student values('101','李軍','男','1976-02-20','95033');
insert into student values('109','王芳','女','1975-02-10','95031');
insert into student values('103','陸君','男','1974-06-03','95031');#添加教師表
insert into teacher values('804','李誠','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','電子工程系');#添加課程表
insert into course values('3-105','計算機導論','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');
#添加成績表insert into score values('103','3-245','86');
insert into score values('105','3-245','75');
insert into score values('109','3-245','68');
insert into score values('103','3-105','92');
insert into score values('105','3-105','88');
insert into score values('109','3-105','76');
insert into score values('103','3-105','64');
insert into score values('105','3-105','91');
insert into score values('109','3-105','78');
insert into score values('103','6-166','85');
insert into score values('105','6-166','79');
insert into score values('109','6-166','81');

?

?

?

1、 查詢Student表中的所有記錄的Sname、Ssex和Class列。

1	select Sname,Ssex,Class from student

2、 查詢教師所有的單位即不重復的Depart列。

1	select distinct Depart from teacher

3、 查詢Student表的所有記錄。

1	select *? from student

4、 查詢Score表中成績在60到80之間的所有記錄。

1	select *? from Score where Degree between 60 and 80

5、 查詢Score表中成績為85，86或88的記錄。

1	select *? from Score where Degree in(85,86,88)

6、 查詢Student表中“95031”班或性別為“女”的同學記錄。

1	select *? from Student where class='95031' or Ssex='女'

7、 以Class降序查詢Student表的所有記錄。

1	select *? from student order by class desc

8、 以Cno升序、Degree降序查詢Score表的所有記錄。

1	select *? from Score order by cno asc,degree desc

9、 查詢“95031”班的學生人數。

1	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）

1	select Sno,Cno? from Score where Degree=(select max(Degree) from Score)

1	select Sno,Cno? from Score order by? Degree desc limit 0,1

11、???? 查詢每門課的平均成績。

1	select Cno,avg(degree) from Score group by Cno

12、???? 查詢Score表中至少有5名學生選修的并以3開頭的課程的平均分數。

1	select avg(Degree) from score where Cno like '3%' and Cno in (select Cno from score group by Cno having count(*)>=5) 用in 不用= 是因為可能會有多個

1	簡單寫法：select avg(Degree) from score where Cno like '3%' and group by Cno having count(*)>=5

13、???? 查詢分數大于70，小于90的Sno列。

1	select Sno from Score where degree>70 and degree<90

14、???? 查詢所有學生的Sname、Cno和Degree列。

1	select? Sname, Cno,Degree from Score , student where Score.Sno=student.Sno

15、???? 查詢所有學生的Sno、Cname和Degree列。

1	select? Sno,Cname,Degree from Score , Course where Score.Cno=Course.Cno

16、???? 查詢所有學生的Sname、Cname和Degree列。

1	select Sname,Cname,Degree from student,course,score where student.Sno=score.Sno and course.Cno=score.Cno

1	join .. on 寫法：select Sname,Cname,Degree from student join score on student.Sno=score.Sno join course on course.Cno=score.Cno

17、???? 查詢“95033”班學生的平均分。

1	select avg(degree) as 'class=95033' 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：

create table grade(low? int(3),upp? int(3),rank? char(1))

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’)

現查詢所有同學的Sno、Cno和rank列。

1	select Sno,Cno,rank from Score,grade where degree between low and upp

19、查詢選修“3-105”課程的成績高于“109”號同學成績的所有同學的記錄。

1	<span style="color: #000000; font-size: 15px">109同學，選修是3-105課的</span>

1	select * from score where Cno='3-105' and degree>(select max(degree ) from Score where Sno='109' and Cno='3-105' )

1	<span style="font-size: 15px">109同學，沒有選修3-105課</span>

1	select * from score where Cno='3-105' and degree>(select max(degree ) from Score where Sno='109')

and degree<( select max(degree ) from Score where sno in (select Sno from score group by Sno having count(*)>1))

1	選了多門課程并且是這個課程下不是最高分的

1	select * from score a where Sno in (select Sno from score group by Sno having count(*)>1) and degree<( select max(degree ) from Score b where b.cno = a.cno)

21、查詢成績高于學號為“109”、課程號為“3-105”的成績的所有記錄。

1	Select * from score where degree>(select degree from Score where Sno='109' and Cno='3-105' )

22、查詢和學號為108、101的同學同年出生的所有學生的Sno、Sname和Sbirthday列。

1	select sno,sname,sbirthday? from student where year(sbirthday) = (select year(sbirthday) from student where? sno='108')

1	select sno,sname,sbirthday? from student where year(sbirthday) = (select year(sbirthday) from student where? sno='101')

23、查詢“張旭“教師任課的學生成績。

1	select Sno,degree from score,Course? where score.Cno=Course.Cno and Course.Tno= (select Tno from Teacher where Tname='張旭' )

1	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5人的教師姓名。

1	select Tname from Teacher,? Course where Teacher.Tno=Course.Tno and Course.Cno =(select Cno from Score group by Cno having count(*)>5)

1	select Tname from Teacher where tno=( select Tno from Course where cno=( select Cno from Score group by Cno having count(*)>5 ))

25、查詢95033班和95031班全體學生的記錄。

1	select * from? student where? class in ('95033','95031')

26、? 查詢存在有85分以上成績的課程Cno.

1	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。

1	select * from course? 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。

1	select Tname,Prof from Teacher where Depart ='計算機系' and Prof? not in( select Prof from Teacher where Depart ='電子工程系')<br>union <br>select Tname,Prof from Teacher where Depart ='電子工程系' and Prof? not in( select Prof from Teacher where Depart ='計算機系')

29、查詢選修編號為“3-105“課程且成績至少高于選修編號為“3-245”的同學的Cno、Sno和Degree,并按Degree從高到低次序排序。

any:代表括號中任意一個成績就可以

1	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

30、查詢選修編號為“3-105”且成績高于選修編號為“3-245”課程的同學的Cno、Sno和Degree.

all:代表括號中的所有成績

1	select Cno,Sno,Degree from score where cno='3-105' and degree >all(select degree from score where cno='3-245' ) order by degree desc

31、?查詢所有教師和同學的name、sex和birthday.

1	select tname,tsex,tbirthday from Teacher union select sname,ssex,sbirthday from Student

32、查詢所有“女”教師和“女”同學的name、sex和birthday.

1	select Tname,Tsex,Tbirthday from Teacher where Tsex='女' union select Sname,Ssex,Sbirthday from Student where Ssex='女'

33、?查詢成績比該課程平均成績低的同學的成績表。

1	select * from score a? where degree < (select avg(degree) from score b where b.cno=a.cno)

34、 查詢所有任課教師的Tname和Depart.

1	select Tname,Depart from Teacher where tno in (select tno from course )

35?、 查詢所有未講課的教師的Tname和Depart.

1	select Tname,Depart from Teacher where Tno not in (select Tno from Course where cno in (select cno from score? ))

36、查詢至少有2名男生的班號。

1	select class from student where ssex='男' group by class having count(*)>1

37、查詢Student表中不姓“王”的同學記錄。

1	select * from Student where Sname not? like '王%%'

38、查詢Student表中每個學生的姓名和年齡。

1	select Sname, year(now())-year(sbirthday)? from Student

39、查詢Student表中最大和最小的Sbirthday日期值。

1	select Max(Sbirthday ),Min(Sbirthday ) 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。

1	select * from Student? order by? class desc, Sbirthday

41、查詢“男”教師及其所上的課程。

1	select Tname,Cname from course,teacher where course.tno= teacher.tno and teacher.Tsex='男'

42、查詢最高分同學的Sno、Cno和Degree列。

1	select Sno,Cno,Degree from score where degree=(select max(degree) from score)

排序寫法：

1	select Sno,Cno,Degree from score order by degree desc limit 0,1

43、查詢和“李軍”同性別的所有同學的Sname.

1	select Sname from Student where Ssex = (select Ssex from Student where Sname='李軍')

44、查詢和“李軍”同性別并同班的同學Sname.

1	select Sname from Student where Ssex = (select Ssex from Student where Sname='李軍' ) and class=( 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。

1	select? Sno,Cno,degree from score where Cno=( select Cno from course where Cname='計算機導論') and Sno in (select Sno from student where Ssex='男')

轉載于:https://www.cnblogs.com/wu-chao/p/9071822.html

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