student表
course表
score表
teacher表
1、 查询Student表中的所有记录的Sname、Ssex和Class列。
select Sname,Ssex,Class from Student;
2、 查询教师所有的单位即不重复的Depart列。
select distinct Depart from Teacher
3、 查询Student表的所有记录。
select * from Student
4、 查询Score表中成绩在60到80之间的所有记录。
select *from Score where Degree between 60 and 80;
5、 查询Score表中成绩为85,86或88的记录。
select *from Score where Degree in(85,86,88);
6、 查询Student表中“95031”班或性别为“女”的同学记录。
select *from Student where Class=95031 or Ssex='女';
7、 以Class降序查询Student表的所有记录。
select *from Student order by Class desc;
8、 以Cno升序、Degree降序查询Score表的所有记录。
select * from Score order by Cno,Degree desc;
9、 查询“95031”班的学生人数。
select COUNT(*) from Student where Class=95031;
10、 查询Score表中的最高分的学生学号和课程号。
select Sno,Cno from Score where Degree=(select MAX(Degree) from Score);
11、 查询每门课的平均成绩。
SELECT cno,AVG(degree) FROM score GROUP BY cno;
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。
SELECT cno,AVG(degree) FROM score GROUP BY cno HAVING COUNT(cno) > 5 AND
cno LIKE '3%';
13、 查询分数大于70,小于90的Sno列。
select Sno from Score where Degree >70 and Degree <90--分数大于70,小于90的Sno列
14、 查询所有学生的Sname、Cno和Degree列。
select Sname, Cno, Degree from Student,Score where Student.Sno = Score.Sno;
15、 查询所有学生的Sno、Cname和Degree列。
select Score.Sno,course.Cname, course.Degree from Score join course on course.cno = score.cno;
16、 查询所有学生的Sname、Cname和Degree列。
select Sname,Cname,Degree from student join Score on Student.Sno=Score.Sno join Course on Score.Cno=Course.Cno
17、 查询“95031”班学生的平均分。
select AVG(degree)from Student join Score on Student.Sno=Score.Sno and Class='95031'
18、 假设使用如下命令建立了一个grade表
现查询所有同学的Sno、Cno和rank列。
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’)
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。
select*from Score where Cno='3-105'and degree>(select degree from score where Sno='109' and Cno='3-105')
20、查询和学号为108、101的同学同年出生的所有学生的Sno、Sname和Sbirthday列。
select sno ,sname,sbirthday from student where
year(sbirthday) = (select year(sbirthday) from student where sno = 101) or
year(sbirthday) = (select year(sbirthday) from student where sno = 108);
21、查询“张旭“教师任课的学生成绩。
select degree from Score where Cno in (select Cno from Course
where Tno in (select Tno from Teacher where Tname = '张旭'))
select degree from Score join Course on Score.Cno=Course.Cno join Teacher on Course.Tno=Teacher.Tno
where Tname = '张旭'
22、查询选修某课程的同学人数多于5人的教师姓名。
select Tname from Teacher
where Tno=(select Tno from Course where Cno=(select Cno from Score group by Cno having COUNT(Cno)>=5))
23、查询95033班和95031班全体学生的记录。
select*from student inner join Score on Student.Sno=Score.Sno where Class in(95033,95031)
select *from Student,Score where Class in(95033,95031) and Student.Sno=Score.Sno
24、 查询存在有85分以上成绩的课程Cno.
select distinct Cno from Score where degree>=85;--去重
25、查询出“计算机系“教师所教课程的成绩表。
select *from Score where Cno in( select Cno from Course
where Tno in (select Tno from Teacher where Depart='计算机系'))
select Sno,Score.Cno,Degree from Score
join Course on Score.Cno=Course.Cno join Teacher on Course.Tno=Teacher.Tno where Depart='计算机系'
26、查询“计算 机系”与“电子工程系“不同职称的教师的Tname和Prof。
select Tname,Prof from Teacher where Prof not in
(select prof from Teacher where Depart='电子工程系' and Prof in (select Prof from Teacher where Depart='计算机系'))
and Depart in ('计算机系','电子工程系')
--查询两个系中教师相同职称名称,不在这里面的就是除去两个系都有的剩下的,见上面
select prof from Teacher where Depart='电子工程系' and Prof in (select Prof from Teacher where Depart='计算机系')
27、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。
select Cno,Sno,Degree from Score a where
(select Degree from Score b where Cno='3-105' and b.Sno=a.Sno)>=
(select Degree from Score c where Cno='3-245' and c.Sno=a.Sno) order by Degree desc
28、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.
select Cno,Sno,Degree from Score a where
(select Degree from Score b where Cno='3-105' and b.Sno=a.Sno)>(select Degree from Score c where Cno='3-245' and c.Sno=a.Sno)
29、 查询所有教师和同学的name、sex和birthday.–表连接,union(纵向连接,表1和表2数据类型要对应且列数对应)上下链接,与join on左右相关链接不同。
select distinct Sname as name,Ssex as sex,Sbirthday as birthday from student
union
select distinct Tname as name,Tsex as sex,Tbirthady as birthday from Teacher
30、查询所有“女”教师和“女”同学的name、sex和birthday.
select distinct Sname as name,Ssex as sex,Sbirthday as birthday from student where Ssex='女'
union
select distinct Tname as name,Tsex as sex,Tbirthady as birthday from Teacher where Tsex='女'
31、查询成绩比该课程平均成绩低的同学的成绩表。–相关子查询–同一门学科的平均分,每门学科低于自身平均分的。
select Sno,Cno,Degree from Score a where a.Degree
32、查询所有任课教师的Tname和Depart.
select Tname,Depart from Teacher
where Tname in (select distinct Tname from Teacher,Course,Score where Teacher.Tno=Course.Tno and Course.Cno=Score.Cno)
select Tname,Depart from Teacher
where tno in (select tno from course where Cno in (select distinct Cno from Score))
33、查询所有未讲课的教师的Tname和Depart.
select Tname,Depart from Teacher
where Tname not in
(select distinct Tname from Teacher,Course,Score where Teacher.Tno=Course.Tno and Course.Cno=Score.Cno)
34、查询至少有2名男生的班号。
select Class FROM student where Ssex='男' group by Class having COUNT(*)>1
35、查询Student表中不姓“王”的同学记录。
select * from student where Sname not like ('王%')
36、查询Student表中每个学生的姓名和年龄。
select Sname,YEAR(GETDATE())-year(Sbirthday) from student
37、查询Student表中最大和最小的Sbirthday日期值。
select MAX(Sbirthday) as 最大,MIN(Sbirthday) as 最小 from student
38、以班号和年龄从大到小的顺序查询Student表中的全部记录。
select * from student order by Class desc,Sbirthday asc
39、查询“男”教师及其所上的课程。
select Tname,Cname from Teacher,Course where Tsex='男' and Teacher.Tno=Course.Tno
40、查询最高分同学的Sno、Cno和Degree列。
select Sno,Cno,Degree from Score where degree=(select MAX(Degree)from Score)
41、查询和“李军”同性别的所有同学的Sname.
select Sname from student where Ssex=(select Ssex from student where Sname='李军') and Sname not in ('李军')
42、查询和“李军”同性别并同班的同学Sname.
select Sname from student where
Ssex=(select Ssex from student where Sname='李军')
and Sname not in ('李军')
and Class=(select Class from student where Sname='李军')
43、查询所有选修“计算机导论”课程的“男”同学的成绩表。
select Sno,Degree from Score
where Sno in (select Sno from student where Ssex='男') and Cno in (select Cno from Course where Cname='计算机导论')