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=85 or degree=86 or degree=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="?";

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(sno) 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 in (select max(degree)from score);?????????????????? //全部課程的最高分
select sno,cno from score a where degree=(select max(degree) from score b where a.cno=b.cno);????????????? //一門課的最高分

11、?查詢每門課的平均成績。

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。

select cno,avg(degree) from score where cno like "3%" group by cno having count(sno)>=5;

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 student.sname,score.cno,score.Degree from student,score where student.Sno=score.Sno;

15、查詢所有學生的Sno、Cname和Degree列。

select score.Sno,course.Cname,score.Degree from course,score where course.cno=score.cno;

16、查詢所有學生的Sname、Cname和Degree列。

select student.Sname,course.Cname,score.Degree from student,course,score where student.sno=score.sno and course.cno=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 score.Sno,score.Cno,grade.rank from score,grade where score.Degree>grade.low and score.degree<grade.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 degree from score where cno="3-105" and sno="109");
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。

//全部成績的最高分：
select * from score where? sno in (select sno from score? group by sno having count(cno)>1)and degree not in (select max(degree) from score);
//每一門的最高分：
select * from score a where sno in (select sno from score group by sno having count(cno)>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。

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 sno,sname,sbirthday from student where 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 degree from score where score.Cno=(select course.Cno from course where course.Tno = (select teacher.Tno from teacher where teacher.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 teacher.tname, course.cname from teacher,course,score where teacher.tno=course.tno and course.cno=score.cno and score.cno= (select cno from score group by cno having count(cno)>5);

25、查詢95033班和95031班全體學生的記錄。

select distinct student.*,score.* from student,score where student.sno=score.sno and student.Class="95033" or student.class="95031" and student.sno=score.sno;

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 * from teacher where depart in('計算機系','電子工程系') group by prof having count(*)=1;

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。

//3-105成績高于選修3-245的所有人分數的同學的3-105成績
select cno,sno,degree from score where cno="3-105"and degree > (select max(degree) from score where cno="3-245")order by degree desc;
//3-105成績高于本人3-245成績的同學的3-105成績
select cno,sno,degree from score a where cno='3-105' and degree> (select degree from score b where cno='3-245' and b.sno=a.sno) 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.

select cno,sno,degree 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 teacher.Tname as name,teacher.Tsex as sex,teacher.Tbirthday as birthday from teacher
union
select student.Sname as name,student.Ssex as sex,student.Sbirthday as birthday from student;

32、查詢所有“女”教師和“女”同學的name、sex和birthday.

select teacher.Tname as name,teacher.Tsex as sex,teacher.Tbirthday as birthday from teacher where tsex='女'
union
select student.Sname as name,student.Ssex as sex,student.Sbirthday as birthday 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。

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 where cno in(select cno from score));
35?、?查詢所有未講課的教師的Tname和Depart.?

select tname,depart from teacher where tno not in(select tno from course where cno 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(sno)>=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,(year(now())-year(sbirthday)) as age from student;

39、查詢Student表中最大和最小的Sbirthday日期值。

select min(sbirthday),max(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 asc;

41、查詢“男”教師及其所上的課程。

select teacher.tname,course.cname from teacher, course? where course.tno=teacher.tno and? teacher.tsex="男";

42、查詢最高分同學的Sno、Cno和Degree列。

select sno,cno,degree from score where degree =(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=(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 a where ssex=(select ssex from student b where sname="李軍"and a.class=b.class);

45、查詢所有選修“計算機導論”課程的“男”同學的成績表。

//法一

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");

//法二
select student.sno,student.sname,score.degree from student,course,score where student.ssex='男' and course.cname='計算機導論' and student.sno=score.sno and course.cno=score.cno;

轉載于:https://www.cnblogs.com/cmzhphp2017/p/7604741.html

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