互聯網 - 大數據

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60到80之間的所有記錄。

select * from Score where Degree>60 and Degree<80

5、 查詢Score表中成績為85，86或88的記錄。

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。

select * from Student where class='95031' or 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,Degree desc

9、 查詢“95031”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)

第二種方法

select sno,cno from score order by degree desc limit 0,1

11、 查詢每門課的平均成績。

select avg(degree),cno 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。

select avg(Degree) from Score where cno in(select cno from score group by cno having count(*)>4) and cno like '3%'

第二種方法
select avg(degree) from score where cno like '3%'group by cno having count(*)>4

13、 查詢分數大于70，小于90的Sno列。

select Sno from Score where Degree>70 and Degree<90

14、 查詢所有學生的Sname、Cno和Degree列。

select Sname,Cno,Degree from Student,Score where Student.Sno=Score.Sno

15、 查詢所有學生的Sno、Cname和Degree列。

select Sno,Cname,Degree from course,Score where course.cno=Score.cno

16、 查詢所有學生的Sname、Cname和Degree列。

select sname,cname,degree from student,course,score where student.sno=score.sno and  course.cno=score.cno

第二種方法
sele sname,cname,degree from student join score on student.sno=score.sno join course on course.con=score.cno

17、 查詢“95033”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：

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。

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。

select * from score where cno='3-105' and degree>(select max(degree) from score where sno='109')

第二種方法
select * from score where cno='3-105' and degree>(select max (degree)form score where sno='109' 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。

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))

第二種方法
select * from score as a where sno in(select sno from score group by sno having count(*)>1) and degree<(select max(degree) from score as 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。

select * from score where degree>(select degree from score where sno='109'and cno='3-105')

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

select * from student year(sbirthday)=(select year(sbirthday) from student where sno='108')

23、查詢“張旭“教師任課的學生成績。

select * 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。

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。

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

 26、  查詢存在有85分以上成績的課程Cno

select distinct 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 depart='計算機系' and prof not in(select prof from teacher where depart='電子工程系' )union
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。

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

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.

select * from score where cno='3-105' and degree>all(select 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,sbirthday 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,sbirthday 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 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.

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.

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

36、查詢至少有2名男生的班號。

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。

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,year(now())-year(sbirthday) from student

39、查詢Student表中最大和最小的Sbirthday日期值。

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。

select * from student order by class desc,sbirthday

41、查詢“男”教師及其所上的課程。

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。

select * from score where degree=(select max(degree) from score)

第二種方法：

select * 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.

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.

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。

select * 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')