题目：设有一数据库，包括四个表：学生表（Student）、课程表（Course）、成绩表（Score）以及教师信息表（Teacher）。

四个表的结构分别如表1-1的表（一）~表（四）所示，数据如表1-2的表（一）~表（四）所示。用SQL语句创建四个表并完成相关题目。

表1-1数据库的表结构

表（一）Student (学生表)

属性名

数据类型

可否为空

含 义

Sno

varchar (20)

否

学号（主码）

Sname

varchar (20)

否

学生姓名

Ssex

varchar (20)

否

学生性别

Sbirthday

datetime

可

学生出生年月

Class

varchar (20)

可

学生所在班级

表（二）Course（课程表）

属性名

数据类型

可否为空

含 义

Cno

varchar (20)

否

课程号（主码）

Cname

varchar (20)

否

课程名称

Tno

varchar (20)

否

教工编号（外码）

表（三）Score(成绩表)

属性名

数据类型

可否为空

含 义

Sno

varchar (20)

否

学号（外码）

Cno

varchar (20)

否

课程号（外码）

Degree

Decimal(4,1)

可

成绩

主码：

表（四）Teacher(教师表)

属性名

数据类型

可否为空

含   义

Tno

varchar (20)

否

教工编号（主码）

Tname

varchar (20)

否

教工姓名

Tsex

varchar (20)

否

教工性别

Tbirthday

datetime

可

教工出生年月

Prof

varchar (20)

可

职称

Depart

varchar (20)

否

教工所在部门

表1-2数据库中的数据

表（一）Student

Sno

Sname

Ssex

Sbirthday

class

108

曾华

男

1977-09-01

95033

105

匡明

男

1975-10-02

95031

107

王丽

女

1976-01-23

95033

101

李军

男

1976-02-20

95033

109

王芳

女

1975-02-10

95031

103

陆君

男

1974-06-03

95031

表（二）Course

Cno

Cname

Tno

3-105

计算机导论

825

3-245

操作系统

804

6-166

数字电路

856

9-888

高等数学

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

李诚

男

1958-12-02

副教授

计算机系

856

张旭

男

1969-03-12

讲师

电子工程系

825

王萍

女

1972-05-05

助教

计算机系

831

刘冰

女

1977-08-14

助教

电子工程系

查询问题：

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

2、 查询教师所有的单位即不重复的Depart列。

3、 查询Student表的所有记录。

4、 查询Score表中成绩在60到80之间的所有记录。

5、 查询Score表中成绩为85，86或88的记录。

6、 查询Student表中“95031”班或性别为“女”的同学记录。

7、 以Class降序查询Student表的所有记录。

8、 以Cno升序、Degree降序查询Score表的所有记录。

9、 查询“95031”班的学生人数。

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）

11、 查询每门课的平均成绩。

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。

13、查询分数大于70，小于90的Sno列。

14、查询所有学生的Sname、Cno和Degree列。

15、查询所有学生的Sno、Cname和Degree列。

16、查询所有学生的Sname、Cname和Degree列

17、 查询“95033”班学生的平均分。

18、 假设使用如下命令建立了一个grade表：

create table grade(low  int,upp  int,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’)

现查询所有同学的Sno、Cno和rank列。

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。

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。

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。

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。

23、查询“张旭“教师任课的学生成绩。

24、查询选修某课程的同学人数多于5人的教师姓名。

25、查询95033班和95031班全体学生的记录。

26、  查询存在有85分以上成绩的课程Cno.

27、查询出“计算机系“教师所教课程的成绩表。

28、查询“计算机系”与“电子工程系“不同职称的教师的Tname和Prof。

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。

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.

31、 查询所有教师和同学的name、sex和birthday.

32、查询所有“女”教师和“女”同学的name、sex和birthday.

33、 查询成绩比该课程平均成绩低的同学的成绩表。

34、 查询所有任课教师的Tname和Depart.

35 、 查询所有未讲课的教师的Tname和Depart.

36、查询至少有2名男生的班号。

37、查询Student表中不姓“王”的同学记录。

38、查询Student表中每个学生的姓名和年龄。

39、查询Student表中最大和最小的Sbirthday日期值。

40、以班号和年龄从大到小的顺序查询Student表中的全部记录。

41、查询“男”教师及其所上的课程。

42、查询最高分同学的Sno、Cno和Degree列。

43、查询和“李军”同性别的所有同学的Sname.

44、查询和“李军”同性别并同班的同学Sname.

45、查询所有选修“计算机导论”课程的“男”同学的成绩表。

create database xuesheng

use xuesheng

go

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)
)

go

create table Teacher
(
Tno varchar(20) not null primary key,
Tname varchar(20) not null,
Tsex varchar(20) not null,
Tbrithday datetime,
Prof varchar(20),
Depart varchar(20) not null
)

go

create table Course
(
Cno varchar(20) not null primary key,
Cname varchar(20) not null,
Tno varchar(20) not null references Teacher(Tno)
)

go

create table Score
(
Sno varchar(20) not null references Student(Sno),
Cno varchar(20) not null references Course(Cno),
Degree Decimal(4,1)
)
alter table Score add constraint pk primary key(Sno, Cno)

  1. 1、select Sname , Ssex , Class from Student 
  2.  
  3. 2、select distinct Depart from Teacher ——去重查询
  4.  
  5. 3、select * from Student 
  6.  
  7. 4、select * from Score where Degree between 60 and 80 ——范围查询，between关键字
  8.  
  9. 5、select * from Score where Degree=85 or Degree=86 or Degree=88
  10.    select * from Score where Degree in(85,86,88)
  11.  
  12. 6、select * from Student where Ssex='女' or Class=95031 ——条件查询
  13.  
  14. 7、select * from Student order  by Class desc
  15.  
  16. 8、select * from Score order  by Cno asc,Degree desc ——排序查询
  17.  
  18. 9、select count(*) from Student where Class=95031
  19.  
  20. 10、select Sno,Cno from score where Degree=(select MAX(Degree) from score)——运用子查询
  21.  
  22. 11、select cno ,AVG(Degree) from Score group by Cno
  23.  
  24. 12、select Cno,avg(Degree) from score  group by Cno having count(Sno)>=5 and Cno like '3%' ——分组查询与模糊查询
  25.     (师)select Cno,avg(Degree) from score where Cno like '3%' group by Cno having count(Sno)>=5 ——聚合函数 count
  26.  
  27. 13、select Sno from Score where Degree between 70 and 90
  28.  
  29. 14、select Sname,Cno,degree from student,score where student.Sno=score.Sno
  30.     (师)select Sname,Cno,degree from score join student on score.sno=student.sno ——连接查询，join  on
  31.  
  32. 15、select Sno,Cname,degree from course,score where course.cno=score.cno
  33.     (师)select Sname,Cno,degree from score join course on score.cno=course.cno
  34.  
  35. 16、select Sname,Cname,degree from student, course,score where student.Sno=score.Sno and course.cno=score.cno
  36.     (师)select Sname,Cno,degree from score join student on score.sno=student.sno join course on score.cno=course.cno
  37.  
  38. 17、select avg(degree) from score where sno in (select sno from student where class='95033') ——离散查询
  39.  
  40. 18、select Sno,Cno,rank from score,grade where score.degree between low and upp
  41.  
  42. 19、select * from score where cno='3-105' and  degree>(select degree from score where sno='109'and cno='3-105')——第一种理解
  43.     select * from score where cno='3-105' and  degree>(select max（degree） from score where sno='109')——理解二
  44.  
  45. 20、select * from score b where degree <(select max(degree) from score a where a.cno=b.cno)
  46.     select * from score  where degree not in (select max(degree) from score  group by cno having count(sno)>1）
  47.  
  48. （师）select * from score where sno in (select sno from score group by sno having count(*)>1) and degree <(select max(degree) from score )
  49.       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 )
  50.  
  51. 21、select * from score where cno='3-105' and  degree>(select degree from score where sno='109'and cno='3-105')
  52.  
  53. 22、select sno,sname,sbirthday from student where datediff(year,sbirthday,getdate())=(select datediff(year,sbirthday,getdate()) from student where sno='108')
  54.       select * from student where year(sbirthdy)=(select year(sbirthday) from student where sno='108')
  55.  
  56. 23、select cno,sno,degree from score where cno=(select cno from course ,teacher  where course.tno=teacher.tno and teacher.tname='张旭')
  57.     (师)select * from score where cno in(select cno from course where tno in(select tno from teacher where tname='张旭'))
  58.  
  59. 24、select  tname from teacher where tno in (select tno from course where cno in (select cno from score group by cno having count(*)>5))
  60.  
  61. 25、select * from student where class in('95033','95031')或者select * from student where class ='95033'or class='95031'
  62.  
  63. 26、select distinct cno from score where degree>85
  64.  
  65. 27、select cno,sno,degree from score where cno in (select cno from course ,teacher  where course.tno=teacher.tno and teacher.depart='计算机系')
  66. （师）select * from score where cno in(select cno from course where tno in(select tno from teacher where depart='计算机系'))
  67.  
  68. 28、select tname,prof from teacher where depart='计算机系' and prof not in (select prof from teacher where depart='电子工程系')
  69.     union
  70.     select tname,prof from teacher where depart='电子工程系' and prof not in (select prof from teacher where depart='计算机系')
  71.  
  72.     select tname,prof from teacher a where prof not in (select prof from teacher b where b.depart != a.depart)
  73.  
  74. 29、select * from score where cno='3-105' and degree>any (select degree from score where cno='3-245')order by degree desc——any其中任何一个、all所有
  75.  
  76. 30、select * from score where cno='3-105' and degree>(select max(degree) from score where cno='3-245')
  77.  
  78. 31、select tname,tsex,tbirthday from teacher
  79.     union
  80.     select sname,ssex,sbirthday from student
  81.  
  82. 32、select tname,tsex,tbirthday from teacher where tsex='女'
  83.     union
  84.     select sname,ssex,sbirthday from student where ssex='女'
  85.  
  86. 33、select * from score a where degree<(select avg(degree)from score b where a.cno=b.cno)
  87.  
  88. 34、select tname,depart from teacher a where exists(select * from course b where a.tno=b.tno);
  89.     select tname,depart from teacher,course where Teacher.tno=Course.tno
  90.     （师）select tname,depart from teacher where tno in( select tno from course where cno in( select distinct cno from score))
  91.  
  92. 35、select tname,depart from teacher a where not exists(select * from course b where a.tno=b.tno);
  93.     （师）select tname,depart from teacher where tno not in( select tno from course where cno in( select distinct cno from score))
  94.  
  95. 36、select class from student where ssex='男'group by class having count(*)>=2;
  96.  
  97. 37、 select * from student where sname not like'王%';
  98.  
  99. 38、select sname as 姓名,datediff(year,sbirthday,getdate()) as 年龄 from student
  100.     select sname as 姓名,year(getdate())-year(sbirthday) as 年龄 from student
  101.  
  102. 39、select sname,sbirthday as 最大 from student where sbirthday =(select min (sbirthday) from student)
  103.     union
  104.     select sname,sbirthday as 最小 from student where sbirthday =(select max(sbirthday) from student)
  105.  
  106.    （师）select min (sbirthday),max(sbirthday) from student
  107.  
  108. 40、select class,sname,sbirthday from student order by class desc,sbirthday;
  109.  
  110. 41、select x.tname,y.cname from teacher x,course y where x.tno=y.tno and x.tsex='男';
  111.     select tname,cname from teacher ,course  where teacher.tno=course.tno and tsex='男'
  112.  
  113. 42、select * from score where degree=(select max(degree)from score);
  114. (师)selsct top 1 * from score order by degree desc——只适用于有一个最高分
  115.  
  116. 43、select sname from student where ssex=(select ssex from student where sname='李军');
  117.  
  118. 44、select sname from student where ssex=(select ssex from student where sname='李军') and class=(select class from student where sname='李军');
  119.  
  120. 45、select * from score where sno in(select sno from student where ssex='男') and cno=(select cno from course where cname='计算机导论');

 

  1. 1、select Sname , Ssex , Class from Student 
  2.  
  3. 2、select distinct Depart from Teacher ——去重查询
  4.  
  5. 3、select * from Student 
  6.  
  7. 4、select * from Score where Degree between 60 and 80 ——范围查询，between关键字
  8.  
  9. 5、select * from Score where Degree=85 or Degree=86 or Degree=88
  10.    select * from Score where Degree in(85,86,88)
  11.  
  12. 6、select * from Student where Ssex='女' or Class=95031 ——条件查询
  13.  
  14. 7、select * from Student order  by Class desc
  15.  
  16. 8、select * from Score order  by Cno asc,Degree desc ——排序查询
  17.  
  18. 9、select count(*) from Student where Class=95031
  19.  
  20. 10、select Sno,Cno from score where Degree=(select MAX(Degree) from score)——运用子查询
  21.  
  22. 11、select cno ,AVG(Degree) from Score group by Cno
  23.  
  24. 12、select Cno,avg(Degree) from score  group by Cno having count(Sno)>=5 and Cno like '3%' ——分组查询与模糊查询
  25.     (师)select Cno,avg(Degree) from score where Cno like '3%' group by Cno having count(Sno)>=5 ——聚合函数 count
  26.  
  27. 13、select Sno from Score where Degree between 70 and 90
  28.  
  29. 14、select Sname,Cno,degree from student,score where student.Sno=score.Sno
  30.     (师)select Sname,Cno,degree from score join student on score.sno=student.sno ——连接查询，join  on
  31.  
  32. 15、select Sno,Cname,degree from course,score where course.cno=score.cno
  33.     (师)select Sname,Cno,degree from score join course on score.cno=course.cno
  34.  
  35. 16、select Sname,Cname,degree from student, course,score where student.Sno=score.Sno and course.cno=score.cno
  36.     (师)select Sname,Cno,degree from score join student on score.sno=student.sno join course on score.cno=course.cno
  37.  
  38. 17、select avg(degree) from score where sno in (select sno from student where class='95033') ——离散查询
  39.  
  40. 18、select Sno,Cno,rank from score,grade where score.degree between low and upp
  41.  
  42. 19、select * from score where cno='3-105' and  degree>(select degree from score where sno='109'and cno='3-105')——第一种理解
  43.     select * from score where cno='3-105' and  degree>(select max（degree） from score where sno='109')——理解二
  44.  
  45. 20、select * from score b where degree <(select max(degree) from score a where a.cno=b.cno)
  46.     select * from score  where degree not in (select max(degree) from score  group by cno having count(sno)>1）
  47.  
  48. （师）select * from score where sno in (select sno from score group by sno having count(*)>1) and degree <(select max(degree) from score )
  49.       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 )
  50.  
  51. 21、select * from score where cno='3-105' and  degree>(select degree from score where sno='109'and cno='3-105')
  52.  
  53. 22、select sno,sname,sbirthday from student where datediff(year,sbirthday,getdate())=(select datediff(year,sbirthday,getdate()) from student where sno='108')
  54.       select * from student where year(sbirthdy)=(select year(sbirthday) from student where sno='108')
  55.  
  56. 23、select cno,sno,degree from score where cno=(select cno from course ,teacher  where course.tno=teacher.tno and teacher.tname='张旭')
  57.     (师)select * from score where cno in(select cno from course where tno in(select tno from teacher where tname='张旭'))
  58.  
  59. 24、select  tname from teacher where tno in (select tno from course where cno in (select cno from score group by cno having count(*)>5))
  60.  
  61. 25、select * from student where class in('95033','95031')或者select * from student where class ='95033'or class='95031'
  62.  
  63. 26、select distinct cno from score where degree>85
  64.  
  65. 27、select cno,sno,degree from score where cno in (select cno from course ,teacher  where course.tno=teacher.tno and teacher.depart='计算机系')
  66. （师）select * from score where cno in(select cno from course where tno in(select tno from teacher where depart='计算机系'))
  67.  
  68. 28、select tname,prof from teacher where depart='计算机系' and prof not in (select prof from teacher where depart='电子工程系')
  69.     union
  70.     select tname,prof from teacher where depart='电子工程系' and prof not in (select prof from teacher where depart='计算机系')
  71.  
  72.     select tname,prof from teacher a where prof not in (select prof from teacher b where b.depart != a.depart)
  73.  
  74. 29、select * from score where cno='3-105' and degree>any (select degree from score where cno='3-245')order by degree desc——any其中任何一个、all所有
  75.  
  76. 30、select * from score where cno='3-105' and degree>(select max(degree) from score where cno='3-245')
  77.  
  78. 31、select tname,tsex,tbirthday from teacher
  79.     union
  80.     select sname,ssex,sbirthday from student
  81.  
  82. 32、select tname,tsex,tbirthday from teacher where tsex='女'
  83.     union
  84.     select sname,ssex,sbirthday from student where ssex='女'
  85.  
  86. 33、select * from score a where degree<(select avg(degree)from score b where a.cno=b.cno)
  87.  
  88. 34、select tname,depart from teacher a where exists(select * from course b where a.tno=b.tno);
  89.     select tname,depart from teacher,course where Teacher.tno=Course.tno
  90.     （师）select tname,depart from teacher where tno in( select tno from course where cno in( select distinct cno from score))
  91.  
  92. 35、select tname,depart from teacher a where not exists(select * from course b where a.tno=b.tno);
  93.     （师）select tname,depart from teacher where tno not in( select tno from course where cno in( select distinct cno from score))
  94.  
  95. 36、select class from student where ssex='男'group by class having count(*)>=2;
  96.  
  97. 37、 select * from student where sname not like'王%';
  98.  
  99. 38、select sname as 姓名,datediff(year,sbirthday,getdate()) as 年龄 from student
  100.     select sname as 姓名,year(getdate())-year(sbirthday) as 年龄 from student
  101.  
  102. 39、select sname,sbirthday as 最大 from student where sbirthday =(select min (sbirthday) from student)
  103.     union
  104.     select sname,sbirthday as 最小 from student where sbirthday =(select max(sbirthday) from student)
  105.  
  106.    （师）select min (sbirthday),max(sbirthday) from student
  107.  
  108. 40、select class,sname,sbirthday from student order by class desc,sbirthday;
  109.  
  110. 41、select x.tname,y.cname from teacher x,course y where x.tno=y.tno and x.tsex='男';
  111.     select tname,cname from teacher ,course  where teacher.tno=course.tno and tsex='男'
  112.  
  113. 42、select * from score where degree=(select max(degree)from score);
  114. (师)selsct top 1 * from score order by degree desc——只适用于有一个最高分
  115.  
  116. 43、select sname from student where ssex=(select ssex from student where sname='李军');
  117.  
  118. 44、select sname from student where ssex=(select ssex from student where sname='李军') and class=(select class from student where sname='李军');
  119.  
  120. 45、select * from score where sno in(select sno from student where ssex='男') and cno=(select cno from course where cname='计算机导论');

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