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sql练习二

 字数 4.6k 

分享一个MySQL（Oracle）数据库sql练习

表结构

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CREATE TABLE STUDENT
(SNO VARCHAR(3) NOT NULL,
SNAME VARCHAR(4) NOT NULL,
SSEX VARCHAR(2) NOT NULL,
SBIRTHDAY DATETIME,
CLASS VARCHAR(5));
CREATE TABLE COURSE
(CNO VARCHAR(5) NOT NULL,
CNAME VARCHAR(10) NOT NULL,
TNO VARCHAR(10) NOT NULL);
CREATE TABLE SCORE
(SNO VARCHAR(3) NOT NULL,
CNO VARCHAR(5) NOT NULL,
DEGREE NUMERIC(10, 1) NOT NULL);
CREATE TABLE TEACHER
(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);

INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (108 ,'曾华','男' ,'1977-09-01',95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明','男' ,'1975-10-02',95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王丽','女' ,'1976-01-23',95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李军','男' ,'1976-02-20',95033);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳','女' ,'1975-02-10',95031);
INSERT INTO STUDENT (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陆君','男' ,'1974-06-03',95031);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('3-105' ,'计算机导论',825);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系统' ,804);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('6-166' ,'数据电路' ,856);
INSERT INTO COURSE(CNO,CNAME,TNO)VALUES ('9-888' ,'高等数学' ,100);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (103,'3-245',86);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-245',75);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-245',68);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (103,'3-105',92);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (105,'3-105',88);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (109,'3-105',76);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'3-105',64);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'3-105',91);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'3-105',78);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (101,'6-166',85);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (107,'6-106',79);
INSERT INTO SCORE(SNO,CNO,DEGREE)VALUES (108,'6-166',81);
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (804,'李诚','男','1958-12-02','副教授','计算机系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (856,'张旭','男','1969-03-12','讲师','电子工程系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (825,'王萍','女','1972-05-05','助教','计算机系');
INSERT INTO TEACHER(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART)
VALUES (831,'刘冰','女','1977-08-14','助教','电子工程系');

题目

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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=85
UNION select * from score where degree=86
union select * from score where degree=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 asc 
select * from score order by 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。
11、查询‘3-105’号课程的平均分。
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、查询最低分大于70，最高分小于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”班所选课程的平均分。
18、假设使用如下命令建立了一个grade表：
create table grade(low   int,upp   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。
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。
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

参考答案一

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1. SELECT SNAME,SSEX,CLASS FROM STUDENT;

2. SELECT DISTINCT DEPART FROM TEACHER;

3. SELECT * FROM STUDENT;

4. SELECT * FROM SCORE WHERE DEGREE BETWEEN 60 AND 80;

5.SELECT * FROM SCORE WHERE DEGREE IN (85,86,88);

6. SELECT * FROM STUDENT WHERE CLASS='95031' OR SSEX='女';

7.SELECT * FROM STUDENT ORDER BY CLASS DESC;

8.SELECT * FROM SCORE ORDER BY CNO ASC,DEGREE DESC;

9.SELECT  COUNT(*) FROM STUDENT WHERE CLASS='95031';

10.SELECT SNO,CNO FROM SCORE WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE);

SELECT SNO,CNO FROM SCORE ORDER BY DEGREE DESC LIMIT 1;

11.SELECT AVG(DEGREE) FROM SCORE WHERE CNO='3-105';

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

13.SELECT SNO FROM SCORE GROUP BY SNO HAVING MIN(DEGREE)>70 AND MAX(DEGREE)<90;

14.SELECT A.SNAME,B.CNO,B.DEGREE FROM STUDENT AS A JOIN SCORE AS B ON A.SNO=B.SNO;

15.SELECT A.CNAME, B.SNO,B.DEGREE FROM COURSE AS A JOIN SCORE AS B ON A.CNO=B.CNO ;

16.SELECT A.SNAME,B.CNAME,C.DEGREE FROM STUDENT A JOIN (COURSE B,SCORE C)
ON A.SNO=C.SNO AND B.CNO =C.CNO;

17.SELECT AVG(A.DEGREE) FROM SCORE A JOIN STUDENT B ON A.SNO = B.SNO WHERE B.CLASS='95033';

18.SELECT A.SNO,A.CNO,B.RANK FROM SCORE A,GRADE B WHERE A.DEGREE BETWEEN B.LOW AND B.UPP 
ORDER BY RANK;

19.SELECT A.* FROM SCORE A JOIN SCORE B WHERE A.CNO='3-105' AND A.DEGREE>B.DEGREE AND 

B.SNO='109' AND B.CNO='3-105';
另一解法：SELECT A.* FROM SCORE A  WHERE A.CNO='3-105' AND A.DEGREE>ALL(SELECT DEGREE FROM 
SCORE B WHERE B.SNO='109' AND B.CNO='3-105');

20.SELECT * FROM score s WHERE DEGREE<(SELECT MAX(DEGREE) FROM SCORE) GROUP BY SNO HAVING 
COUNT(SNO)>1 ORDER BY DEGREE ;

21.见19的第二种解法

22.SELECT SNO,SNAME,SBIRTHDAY FROM STUDENT WHERE YEAR(SBIRTHDAY)=(SELECT YEAR(SBIRTHDAY) 
FROM STUDENT WHERE SNO='108');
Oracle:select x.cno,x.Sno,x.degree from score x,score y where x.degree>y.degree and 
y.sno='109'and y.cno='3-105';
select cno,sno,degree from score   where degree >(select degree from score where sno='109' 
and cno='3-105')

23.SELECT A.SNO,A.DEGREE FROM SCORE A JOIN (TEACHER B,COURSE C)
ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.TNAME='张旭';
另一种解法：select cno,sno,degree from score where cno=(select x.cno from course x,teacher y 
where x.tno=y.tno and y.tname='张旭');
根据实际EXPLAIN此SELECT语句，第一个的扫描次数要小于第二个

24.SELECT A.TNAME FROM TEACHER A JOIN (COURSE B, SCORE C) ON (A.TNO=B.TNO AND B.CNO=C.CNO) 
GROUP BY C.CNO HAVING COUNT(C.CNO)>5;
另一种解法：select tname from teacher where tno in(select x.tno from course x,score y where 
x.cno=y.cno group by x.tno having count(x.tno)>5);
实际测试1明显优于2

25.select cno,sno,degree from score where cno=(select x.cno from course x,teacher y where 
x.tno=y.tno and y.tname='张旭');

26.SELECT CNO FROM SCORE GROUP BY CNO HAVING MAX(DEGREE)>85;
另一种解法：select distinct cno from score where degree in (select degree from score where 
degree>85);

27.SELECT A.* FROM SCORE A JOIN (TEACHER B,COURSE C) ON A.CNO=C.CNO AND B.TNO=C.TNO
WHERE B.DEPART='计算机系';
另一种解法：SELECT * from score where cno in (select a.cno from course a join teacher b on 
a.tno=b.tno and b.depart='计算机系');
此时2略好于1，在多连接的境况下性能会迅速下降

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');

29.SELECT * FROM SCORE WHERE DEGREE>ANY(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER 
BY DEGREE DESC;

30.SELECT * FROM SCORE WHERE DEGREE>ALL(SELECT DEGREE FROM SCORE WHERE CNO='3-245') ORDER 
BY DEGREE DESC;

31.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER;

32.SELECT SNAME AS NAME, SSEX AS SEX, SBIRTHDAY AS BIRTHDAY FROM STUDENT WHERE SSEX='女'
UNION
SELECT TNAME AS NAME, TSEX AS SEX, TBIRTHDAY AS BIRTHDAY FROM TEACHER WHERE TSEX='女';

33.SELECT A.* FROM SCORE A WHERE DEGREE<(SELECT AVG(DEGREE) FROM SCORE B WHERE A.CNO=B.CNO);
须注意********此题

34.解法一：SELECT A.TNAME,A.DEPART FROM TEACHER A JOIN COURSE B ON A.TNO=B.TNO;
解法二：select tname,depart from teacher a where exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO IN (SELECT TNO FROM COURSE);
实际分析，第一种揭发貌似更好，至少扫描次数最少。

35.解法一：SELECT TNAME,DEPART FROM TEACHER A LEFT JOIN COURSE B USING(TNO) WHERE ISNUL
(B.tno);
解法二：select tname,depart from teacher a where not exists
(select * from course b where a.tno=b.tno);
解法三：SELECT TNAME,DEPART FROM TEACHER WHERE TNO NOT IN (SELECT TNO FROM COURSE);
NOT IN的方法效率最差，其余两种差不多

36.SELECT CLASS FROM STUDENT A WHERE SSEX='男' GROUP BY CLASS HAVING COUNT(SSEX)>1;

37.SELECT * FROM STUDENT A WHERE SNAME not like '王%';

38.SELECT SNAME,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT;

39.select sname,sbirthday as THEMAX from student where sbirthday =(select min(SBIRTHDAY) 
from student)
union
select sname,sbirthday as THEMIN from student where sbirthday =(select max(SBIRTHDAY) from 
student);

40.SELECT CLASS,(YEAR(NOW())-YEAR(SBIRTHDAY)) AS AGE FROM STUDENT ORDER BY CLASS DESC,AGE 
DESC;

41.SELECT A.TNAME,B.CNAME FROM TEACHER A JOIN COURSE B USING(TNO) WHERE A.TSEX='男';

42.SELECT A.* FROM SCORE A WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE B );

43.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李军');

44.SELECT SNAME FROM STUDENT A WHERE SSEX=(SELECT SSEX FROM STUDENT B WHERE B.SNAME='李军' )
AND CLASS=(SELECT CLASS FROM STUDENT C WHERE c.SNAME='李军');

45.解法一：SELECT A.* FROM SCORE A JOIN (STUDENT B,COURSE C) USING(sno,CNO) WHERE B.SSEX='男' 
AND C.CNAME='计算机导论';
解法二：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');

参考答案二

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#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 ssex = '女' OR class = '95031'
#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‘3-105’号课程的平均分。
SELECT AVG(degree) FROM score WHERE cno = '3-105'
#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 AVG(degree) FROM score GROUP BY cno HAVING COUNT(sno) >= 5
AND cno LIKE '3%'
#13、查询最低分大于70，最高分小于90的Sno列。
SELECT sno FROM score GROUP BY sno
HAVING MIN(degree) > 70 AND MAX(degree) < 90
#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 sno,cname,degree FROM course, score
WHERE course.cno = score.cno
#16、查询所有学生的Sname、Cname和Degree列。
SELECT sname, cname, degree
FROM score,course,student
WHERE student.SNO = score.SNO
AND score.CNO = course.CNO
#17、查询“95033”班所选课程的平均分。
SELECT cno,AVG(degree) FROM score WHERE sno IN 
(SELECT sno FROM student WHERE class = '95033')
GROUP BY cno

SELECT AVG(degree) FROM score
WHERE sno IN (SELECT sno FROM student WHERE class = '95033')
#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');
COMMIT;
#现查询所有同学的Sno、Cno和rank列。
SELECT o.sno,o.cno,g.rank
FROM score o,grade g
WHERE degree BETWEEN low AND upp
#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 score ,
(
SELECT cno ,MAX(degree) AS maxd
FROM score
GROUP BY cno
) a
WHERE sno IN 
(
SELECT sno
FROM score 
GROUP BY sno
HAVING COUNT(*) > 1
) 
AND score.cno = a.cno 
AND score.degree != a.maxd

SELECT * 
FROM score a
WHERE sno IN 
(
SELECT b.sno
FROM score b
GROUP BY b.sno
HAVING COUNT(*) > 1
) 
AND a.degree !=
(
SELECT MAX(c.degree)
FROM score c
WHERE c.cno = a.cno
)
#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 score
WHERE degree > 
(
SELECT degree
FROM score
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 a.sno ,a.sname,a.sbirthday
FROM student a,student b
WHERE YEAR(a.sbirthday) = YEAR(b.sbirthday)
AND b.sno = '108' 
AND a.sno != '108'

SELECT sno ,sname,sbirthday
FROM student
WHERE YEAR(sbirthday) = 
(SELECT YEAR(sbirthday)
FROM student 
WHERE sno = '108'
)
AND sno != '108'
#23、查询“张旭“教师任课的学生成绩。
SELECT sno,degree
FROM score,teacher,course
WHERE score.CNO = course.CNO
AND teacher.tno = course.TNO
AND 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 DISTINCT teacher.TNAME
FROM course,teacher,score
WHERE teacher.TNO = course.TNO
AND course.cno = score.CNO
AND course.cno IN
(
SELECT cno 
FROM score
GROUP BY cno
HAVING COUNT(sno) > 5
)
#25、查询95033班和95031班全体学生的记录。
SELECT * 
FROM student 
WHERE class = '95033'
OR class = '95031'
ORDER BY class
#26、查询存在有85分以上成绩的课程Cno.
SELECT DISTINCT cno
FROM score
WHERE degree > 85
#27、查询出“计算机系“教师所教课程的成绩表。
SELECT tname,cname,degree,sno
FROM score,course,teacher
WHERE score.CNO = course.CNO
AND teacher.TNO = course.TNO
AND 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 * 
FROM
((
SELECT tname AS ctname,prof AS cprof
FROM teacher
WHERE depart = '计算机系'
) a,
(
SELECT tname AS etname,prof AS eprof
FROM teacher
WHERE depart = '电子工程系'
) b)
WHERE a.cprof != b.eprof

SELECT tname,prof
FROM teacher
WHERE depart IN ('计算机系','电子工程系')
GROUP BY prof
HAVING COUNT(*) < 2
#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 * 
FROM
(
(
SELECT *
FROM score
WHERE cno = '3-105'
)  a,
(
SELECT *
FROM score
WHERE cno = '3-245'
) b
)
WHERE a.sno = b.sno
AND a.degree > b.degree
ORDER BY a.degree DESC

SELECT Cno,Sno,Degree 
FROM score 
WHERE cno = '3-105'
AND degree > 
(
SELECT MIN(degree) 
FROM score
WHERE cno = '3-245'
)
ORDER BY degree DESC
#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 score 
WHERE cno = '3-105'
AND degree > 
(
SELECT MAX(degree) 
FROM score
WHERE cno = '3-245'
)
#31、查询所有教师和同学的name、sex和birthday.
SELECT tname,tsex,tbirthday
FROM teacher
UNION
SELECT sname,ssex,sbirthday
FROM student
#32、查询所有“女”教师和“女”同学的name、sex和birthday.
SELECT sname,ssex,sbirthday
FROM student
WHERE ssex = '女'
UNION
SELECT tname,tsex,tbirthday
FROM teacher
WHERE tsex = '女'
#33、查询成绩比该课程平均成绩低的同学的成绩表。
SELECT * 
FROM score s1,
(
SELECT cno,AVG(degree) AS a
FROM score
GROUP BY cno
) s2
WHERE degree < s2.a 
AND s1.cno = s2.cno

#34、查询所有任课教师的Tname和Depart.
SELECT DISTINCT tname,depart
FROM teacher,course,score
WHERE teacher.TNO = course.TNO
AND course.CNO = score.CNO
#35  查询所有未讲课的教师的Tname和Depart. 
SELECT tname,depart
FROM teacher
WHERE tno NOT IN 
(
SELECT DISTINCT teacher.tno
FROM teacher,course,score
WHERE teacher.TNO = course.TNO
AND course.CNO = score.CNO
)
#36、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
#37、查询Student表中不姓“王”的同学记录。
SELECT * 
FROM student 
WHERE sname NOT LIKE '王%'
#38、查询Student表中每个学生的姓名和年龄。
SELECT sname,2019 - YEAR(sbirthday)
FROM student
#39、查询Student表中最大和最小的Sbirthday日期值。
SELECT MAX(sbirthday),MIN(sbirthday)
FROM student
#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 * 
FROM student
ORDER BY class DESC,SBIRTHDAY
#41、查询“男”教师及其所上的课程。
SELECT tname,cname
FROM teacher ,course
WHERE teacher.TNO = course.TNO
AND tsex = '男'
#42、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
)
#43、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 != '李军'
#44、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 != '李军'
AND class IN 
(
SELECT class 
FROM student
WHERE 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 * 
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'
)
文章作者: akbcd
文章链接: https://akbcd.github.io/2019/12/08/sql练习二/
版权声明: 本博客所有文章除特別声明外，均采用 CC BY 4.0 许可协议。转载请注明来源 akbcd !

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