[转] 经典SQL练习题

原题目来自qaz13177_58_CSDN博客 http://blog.csdn.net/qaz13177_58_/article/details/5575711/#sql

只是更新个人答案供参考

表结构：
CREATE TABLE STUDENT
(SNO VARCHAR(3) NOT NULL, 
SNAME VARCHAR(4) NOT NULL,
SSEX VARCHAR(2) NOT NULL, 
SBIRTHDAY DATETIME,
CLASS VARCHAR(5))
go
CREATE TABLE COURSE
(CNO VARCHAR(5) NOT NULL, 
CNAME VARCHAR(10) NOT NULL, 
TNO VARCHAR(10) NOT NULL)
go
CREATE TABLE SCORE 
(SNO VARCHAR(3) NOT NULL, 
CNO VARCHAR(5) NOT NULL, 
DEGREE NUMERIC(10, 1) NOT NULL) 
go
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);
GO
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);
GO
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);
GO
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：
1、 查询Student表中的所有记录的Sname、Ssex和Class列。
2、 查询教师所有的单位即不重复的Depart列。
3、 查询Student表的所有记录。
4、 查询Score表中成绩在60到80之间的所有记录。
5、 查询Score表中成绩为85，86或88的记录。
6、 查询Student表中“95031”班或性别为“女”的同学记录。
7、 以Class降序查询Student表的所有记录。
8、 以Cno升序、Degree降序查询Score表的所有记录。
9、 查询“95031”班的学生人数。
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   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。
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
个人答案(没有验证,有误请指出,仅为复习语法,不考虑性能以及合理性)：

SELECT * FROM dbo.COURSE
SELECT * FROM dbo.SCORE
SELECT * FROM dbo.STUDENT
SELECT * FROM dbo.TEACHER
SELECT * FROM grade

--答案主要使用飞相关子查询完成(因为效率比较高),相关子查询多用JOIN语句代替,但也有写到
--相关子查询的地方,仅只是为了锻炼更多种写法

1.SELECT SNAME,SSEX,CLASS FROM STUDENT

2.SELECT COUNT(*) AS 老师数量,DEPART FROM TEACHER GROUP BY DEPART

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 SSEX='女' OR CLASS='95031'

7.SELECT * FROM STUDENT ORDER BY CLASS DESC

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

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

10.SELECT SNO,CNO FROM SCORE WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE)
SELECT TOP 1 SNO,CNO FROM SCORE ORDER BY DEGREE DESC

11.SELECT CONVERT(DECIMAL(10,2),AVG(DEGREE)) FROM SCORE WHERE CNO='3-105'/

12.WITH T_C AS(SELECT CNO FROM SCORE WHERE CNO LIKE '3%' GROUP BY CNO HAVING COUNT(CNO)>5)
SELECT AVG(DEGREE) AS '五名以上学生选修并且3开头的所有课程的所有得分平均数' 
FROM SCORE WHERE CNO IN (SELECT T_C.CNO FROM T_C)

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

14.SELECT *,(SELECT SNAME FROM STUDENT S WHERE S.SNO=SCORE.SNO) AS 学生姓名 FROM SCORE ORDER BY SNO

15.SELECT *,(SELECT CNAME FROM COURSE S WHERE S.CNO=SCORE.CNO) AS 课程 FROM SCORE ORDER BY SNO

16.SELECT DEGREE AS 成绩,
(SELECT SNAME FROM STUDENT S WHERE S.SNO=SCORE.SNO) AS 学生姓名,
(SELECT CNAME FROM COURSE T WHERE T.CNO=SCORE.CNO) AS 课程  FROM SCORE ORDER BY 学生姓名

17.SELECT AVG(DEGREE) FROM SCORE WHERE SNO IN (SELECT SNO FROM STUDENT WHERE CLASS='95033')

18.SELECT SNO,CNO,(SELECT RANK FROM grade G WHERE DEGREE BETWEEN G.low AND G.upp) AS RANK FROM SCORE

19.SELECT * FROM SCORE WHERE CNO='3-105' AND DEGREE>(SELECT TOP 1 DEGREE FROM SCORE WHERE CNO='3-105' AND SNO=109)

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

21.SELECT * FROM SCORE WHERE CNO='3-105' AND DEGREE>(SELECT TOP 1 DEGREE FROM SCORE WHERE CNO='3-105' AND SNO=109)

22.SELECT SNO,SNAME,SBIRTHDAY FROM STUDENT WHERE DATEPART(YYYY,SBIRTHDAY)=(SELECT TOP 1 DATEPART(YYYY,SBIRTHDAY) FROM STUDENT WHERE SNO=108)

23.SELECT * FROM SCORE WHERE CNO=(SELECT CNO FROM COURSE WHERE TNO=(SELECT TOP 1 TNO FROM TEACHER WHERE TNAME='张旭'))

24.
WITH TEMP AS
(
  SELECT CNO,COUNT(CNO) AS StuCount FROM SCORE GROUP BY CNO HAVING COUNT(CNO)>5
)
SELECT TNAME AS 教师姓名,C.CNAME AS 课程,TEMP.StuCount AS 报修人数
FROM TEACHER T LEFT JOIN COURSE C ON T.TNO=C.TNO INNER JOIN TEMP ON C.CNO=TEMP.CNO

25.SELECT * FROM STUDENT WHERE CLASS IN ('95033','95031')

26.SELECT DISTINCT CNO FROM SCORE WHERE DEGREE>85

27.SELECT * FROM SCORE S WHERE EXISTS
((SELECT CNO FROM COURSE WHERE TNO IN (SELECT TNO FROM TEACHER WHERE DEPART='计算机系')
 AND CNO=S.CNO)) --仅做锻炼使用exists关键字 exists 与 in 的区别在于 
                 --in先执行内层 exists先执行外层 
                 --所以根据父子查询的数据量 两个关键字会有不同的性能高低  
                 --因此不能准确说明 in 与 ex 的效率高低

28.
SELECT * FROM TEACHER WHERE PROF NOT IN
(
 SELECT T1.PROF FROM 
 (SELECT PROF FROM TEACHER WHERE DEPART='计算机系') T1 INNER JOIN 
 (SELECT PROF FROM TEACHER WHERE DEPART='电子工程系') T2 ON T1.PROF=T2.PROF
)--这题我理解是不是有问题

29.SELECT * FROM SCORE WHERE CNO='3-105' AND DEGREE>(SELECT MAX(DEGREE)FROM SCORE WHERE CNO='3-245') ORDER BY DEGREE DESC

30.SELECT * FROM SCORE WHERE CNO='3-105' AND DEGREE>(SELECT MAX(DEGREE)FROM SCORE WHERE CNO='3-245') 

31.
SELECT '学生' AS 姓名,'' AS 性别,NULL AS 生日 UNION ALL
SELECT SNAME,SSEX,SBIRTHDAY FROM STUDENT UNION ALL
SELECT '老师','',NULL UNION ALL
SELECT TNAME,TSEX,TBIRTHDAY FROM TEACHER

32.
SELECT '学生' AS 姓名,'' AS 性别,NULL AS 生日 UNION ALL
SELECT SNAME,SSEX,SBIRTHDAY FROM STUDENT WHERE SSEX='女' UNION ALL
SELECT '老师','',NULL UNION ALL
SELECT TNAME,TSEX,TBIRTHDAY FROM TEACHER WHERE TSEX='女'

33.SELECT * FROM SCORE T WHERE DEGREE>(SELECT AVG(DEGREE) AS AVGS FROM SCORE WHERE CNO=T.CNO GROUP BY CNO)

34.SELECT TNAME,DEPART FROM TEACHER T WHERE EXISTS(SELECT * FROM COURSE WHERE TNO=T.TNO)

35.SELECT TNAME,DEPART FROM TEACHER T WHERE NOT EXISTS(SELECT * FROM COURSE WHERE TNO=T.TNO)

36.SELECT CLASS FROM STUDENT WHERE SSEX='男' GROUP BY CLASS HAVING COUNT(SSEX)>=2

37.SELECT * FROM STUDENT WHERE LTRIM(SNAME) NOT LIKE '王%'

38.SELECT SNAME,DATEDIFF(YEAR,SBIRTHDAY,GETDATE()) AS 年龄,SBIRTHDAY FROM STUDENT

39.
SELECT '最大值:'+CONVERT(NVARCHAR(200),MAX(SBIRTHDAY),23) FROM STUDENT  UNION
SELECT '最小值:'+CONVERT(NVARCHAR(200),MIN(SBIRTHDAY),23) FROM STUDENT 

40.
SELECT * FROM STUDENT ORDER BY CLASS,SBIRTHDAY --班级号优先
SELECT * FROM STUDENT ORDER BY SBIRTHDAY,CLASS --年龄大优先

41.SELECT * FROM TEACHER T INNER JOIN COURSE C ON T.TNO=C.TNO AND T.TSEX='男'

42.
SELECT TOP 1 * FROM SCORE ORDER BY DEGREE DESC --这是错误的,如果2位同学并列呢
SELECT * FROM SCORE WHERE DEGREE=(SELECT MAX(DEGREE) FROM SCORE )

43.
DECLARE @SEX NVARCHAR(2)
SET @SEX=(SELECT TOP 1 SSEX FROM STUDENT WHERE SNAME='李军')
SELECT * FROM STUDENT WHERE SSEX=@SEX
SELECT * FROM STUDENT WHERE SSEX=(SELECT TOP 1 SSEX FROM STUDENT WHERE SNAME='李军')

44.
SELECT * FROM STUDENT 
WHERE SSEX=(SELECT TOP 1 SSEX FROM STUDENT WHERE SNAME='李军')
AND CLASS=(SELECT TOP 1 CLASS FROM STUDENT WHERE SNAME='李军')

45.
SELECT * FROM STUDENT WHERE SSEX='男'
AND SNO IN
(SELECT DISTINCT SNO FROM SCORE WHERE CNO=(SELECT TOP 1 CNO FROM COURSE WHERE CNAME='计算机导论'))