sql练习03

准备数据
建表语句
CREATE TABLE students
(sno VARCHAR(3) NOT NULL,
sname VARCHAR(4) NOT NULL,
ssex VARCHAR(2) NOT NULL,
sbirthday DATETIME,
class VARCHAR(5))

CREATE TABLE courses
(cno VARCHAR(5) NOT NULL,
cname VARCHAR(10) NOT NULL,
tno VARCHAR(10) NOT NULL)

CREATE TABLE scores
(sno VARCHAR(3) NOT NULL,
cno VARCHAR(5) NOT NULL,
degree NUMERIC(10, 1) NOT NULL)

CREATE TABLE teachers
(tno VARCHAR(3) NOT NULL,
tname VARCHAR(4) NOT NULL, tsex VARCHAR(2) NOT NULL,
tbirthday DATETIME NOT NULL, prof VARCHAR(6),
depart VARCHAR(10) NOT NULL)

插入数据
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (108 ,'曾华' ,'男' ,'1977-09-01',95033);
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明' ,'男' ,'1975-10-02',95031);
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王丽' ,'女' ,'1976-01-23',95033);
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李军' ,'男' ,'1976-02-20',95033);
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳' ,'女' ,'1975-02-10',95031);
INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陆君' ,'男' ,'1974-06-03',95031);

INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-105' ,'计算机导论',825);
INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系统' ,804);
INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('6-166' ,'数据电路' ,856);
INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('9-888' ,'高等数学' ,100);

INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-245',86);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-245',75);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-245',68);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-105',92);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-105',88);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-105',76);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'3-105',64);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'3-105',91);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'3-105',78);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'6-166',85);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'6-106',79);
INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'6-166',81);

INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (804,'李诚','男','1958-12-02','副教授','计算机系');
INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (856,'张旭','男','1969-03-12','讲师','电子工程系');
INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (825,'王萍','女','1972-05-05','助教','计算机系');
INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (831,'刘冰','女','1977-08-14','助教','电子工程系');

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

select Sname,Ssex,Class from students;
2、 查询教师所有的单位即不重复的Depart列。

select distinct depart from teachers;
3、 查询Student表的所有记录。

select * from scores where 60<degree and degree<80;
4、 查询Score表中成绩在60到80之间的所有记录。

select * from scores where degree in(85,86,88);
5、 查询Score表中成绩为85，86或88的记录。

select * from students where class = "95031" or ssex = "女";
6、 查询Student表中“95031”班或性别为“女”的同学记录。

select * from students ORDER BY class DESC;
7、 以Class降序查询Student表的所有记录。

select * from scores ORDER BY cno,degree Desc;
8、 以Cno升序、Degree降序查询Score表的所有记录。

select count(*) from students where class = "95031";
9、 查询“95031”班的学生人数。

select sno,cno from scores where degree=(SELECT max(degree) from scores);
10、查询Score表中的最高分的学生学号和课程号。

select AVG(degree) from scores where cno="3-105";
11、查询‘3-105’号课程的平均分。

select avg(degree) from scores where cno like "3%" group by cno having count(sno)>=5; 
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 sno from scores where (select max(degree) from scores)<90 and (select min(degree) from scores)>70;
13、查询最低分大于70，最高分小于90的Sno列。

select sno from scores group by degree having max(degree)<90 and min(degree)>70;
14、查询所有学生的Sname、Cno和Degree列。

select A.sname,B.cno,B.degree
from students A
join scores B
on A.sno = B.sno;

15、查询所有学生的Sno、Cname和Degree列。

select A.cname,B.sno,B.degree
from courses A
join scores B
on A.cno = B.cno;

16、查询所有学生的Sname、Cname和Degree列。

select A.sname,B.degree,C.cname
from students A
join scores B
on A.sno=B.sno
join courses C
on B.cno=C.cno;

17、查询“95033”班所选课程的平均分。

select C.cname,avg(B.degree)
from students A
join scores B
on A.sno=B.sno
join courses C
on B.cno=C.cno
where A.class="95033"
group by C.cno
ORDER BY C.cname;

18、假设使用如下命令建立了一个grade表：
create table grade(low number(3,0),upp number(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’);
commit;
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。

select A.*,B.degree
from students A
join scores B
on A.sno=B.sno
where B.cno="3-105"
and B.degree>(select degree from scores where sno="109" and cno="3-105");

20、查询score中选学一门以上课程的同学中分数为非最高分成绩的记录。

select *
from scores
GROUP BY sno
having degree!=max(degree)
and count(cno)>1;

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。

select *
from scores
where degree>(select degree from scores where sno="109" and cno="3-105");

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。

SELECT s1.Sno,s1.Sname,s1.Sbirthday
FROM Students AS s1 INNER JOIN Students AS s2
ON(YEAR(s1.Sbirthday)=YEAR(s2.Sbirthday))
WHERE s2.Sno='108'
and s1.sno!="108";

23、查询“张旭“教师任课的学生成绩。

select C.*
from teachers A
join courses B
on A.tno=B.tno
join scores C
on B.cno=C.cno
where A.tname="张旭";

24、查询选修某课程的同学人数多于5人的教师姓名。

select A.*
from teachers A
join courses B
on A.tno=B.tno
join scores C
on B.cno=C.cno
GROUP BY C.cno
having count(C.cno)>5;

25、查询95033班和95031班全体学生的记录。

select *
from students
where class in("95033","95031");

26、查询存在有85分以上成绩的课程Cno.

select cno
from scores
where degree>85;

27、查询出“计算机系“教师所教课程的成绩表。

select C.degree
from teachers A
join courses B
on A.tno=B.tno
join scores C
on B.cno=C.cno
where A.depart="计算机系";

28、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 teachers
where depart
in('计算机系','电子工程系')
GROUP BY 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。

select cno,sno,degree
from scores
where cno="3-105"
and degree>=any(select degree from scores where cno="3-245")
order by degree;

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.

select cno,sno,degree
from scores
where cno="3-105"
and degree>=all(select degree from scores where cno="3-245");

31、查询所有教师和同学的name、sex和birthday.

SELECT Sname,Ssex,Sbirthday
FROM Students
UNION
SELECT Tname,Tsex,Tbirthday
FROM Teachers;

32、查询所有“女”教师和“女”同学的name、sex和birthday.

SELECT Sname,Ssex,Sbirthday
FROM Students
where ssex="女"
UNION
SELECT Tname,Tsex,Tbirthday
FROM Teachers
where tsex="女";

33、查询成绩比该课程平均成绩低的同学的成绩表。

select A.*
from scores A
join (select cno,avg(degree) avgd from scores group by cno) B
on (A.cno=B.cno and A.degree<B.avgd);

34、查询所有任课教师的Tname和Depart.

select tname,depart
from teachers
where tno in(select tno from scores);

35 查询所有未讲课的教师的Tname和Depart.

select tname,depart
from teachers
where tno not in(select tno from scores);

36、查询至少有2名男生的班号。

SELECT Class,COUNT(1) AS boyCount
FROM Students
WHERE Ssex='男'
GROUP BY Class
HAVING boyCount>=2;

37、查询Student表中不姓“王”的同学记录。

select *
from students
where sname not like "王%";

38、查询Student表中每个学生的姓名和年龄。

select sname,year(now())-year(sbirthday) as age
from students;

39、查询Student表中最大和最小的Sbirthday日期值。

select max(sbirthday),min(sbirthday)
from students;

40、以班号和年龄从大到小的顺序查询Student表中的全部记录。

select *,year(now())-year(sbirthday) as age
from students
order by class desc,age desc;

41、查询“男”教师及其所上的课程。

select A.tname,B.cname
from teachers A
join courses B
on A.tno=B.tno
where A.tsex="男";

42、查询最高分同学的Sno、Cno和Degree列。

select *
from scores
where degree=(select max(degree) from scores);

43、查询和“李军”同性别的所有同学的Sname.

select sname
from students
where ssex=(select ssex from students where sname="李军")
and sname!="李军";

44、查询和“李军”同性别并同班的同学Sname.

select sname
from students
where ssex=(select ssex from students where sname="李军")
and class=(select class from students where sname="李军")
and sname!="李军";

45、查询所有选修“计算机导论”课程的“男”同学的成绩表

select B.*
from students A
join scores B
on A.sno=B.sno
join courses C
on B.cno=C.cno
where C.cname="计算机导论"
and A.ssex="男";