50个经典SQL题目

柔情只为你懂 2021-11-26 19:18 286阅读 0赞

Student(S\#,Sname,Sage,Ssex) 学生表

Course(C\#,Cname,T\#) 课程表

SC(S\#,C\#,score) 成绩表

Teacher(T\#,Tname) 教师表

问题：

1、查询“001”课程比“002”课程成绩高的所有学生的学号；

select a.S\# from (select s\#,score from SC where C\#='001') a,(select s\#,score

from SC where C\#='002') b

where a.score>b.score and a.s\#=b.s\#;

2、查询平均成绩大于60分的同学的学号和平均成绩；

select S\#,avg(score)

from sc

group by S\# having avg(score) >60;

3、查询所有同学的学号、姓名、选课数、总成绩；

select Student.S\#,Student.Sname,count(SC.C\#),sum(score)

from Student left Outer join SC on Student.S\#=SC.S\#

group by Student.S\#,Sname

4、查询姓“李”的老师的个数；

select count(distinct(Tname))

from Teacher

where Tname like '李%';

5、查询没学过“叶平”老师课的同学的学号、姓名；

select Student.S\#,Student.Sname

from Student

where S\# not in (select distinct( SC.S\#) from SC,Course,Teacher where SC.C\#=Course.C\# and Teacher.T\#=Course.T\# and Teacher.Tname='叶平');

6、查询学过“001”并且也学过编号“002”课程的同学的学号、姓名；

select Student.S\#,Student.Sname from Student,SC where Student.S\#=SC.S\# and SC.C\#='001'and exists( Select \* from SC as SC\_2 where SC\_2.S\#=SC.S\# and SC\_2.C\#='002');

7、查询学过“叶平”老师所教的所有课的同学的学号、姓名；

select S\#,Sname

from Student

where S\# in (select S\# from SC ,Course ,Teacher where SC.C\#=Course.C\# and Teacher.T\#=Course.T\# and Teacher.Tname='叶平' group by S\# having count(SC.C\#)=(select count(C\#) from Course,Teacher where Teacher.T\#=Course.T\# and Tname='叶平'));

8、\[url=\]查询课程编号“002”的成绩比课程编号“001”课程低的所有同学的学号、姓名；\[/url\]

Select S\#,Sname from (select Student.S\#,Student.Sname,score ,(select score from SC SC\_2 where SC\_2.S\#=Student.S\# and SC\_2.C\#='002') score2

from Student,SC where Student.S\#=SC.S\# and C\#='001') S\_2 where score2 <score;

9、查询所有课程成绩小于60分的同学的学号、姓名；

select S\#,Sname

from Student

where S\# not in (select Student.S\# from Student,SC where S.S\#=SC.S\# and score>60);

10、查询没有学全所有课的同学的学号、姓名；

select Student.S\#,Student.Sname

from Student,SC

where Student.S\#=SC.S\# group by Student.S\#,Student.Sname having count(C\#) <(select count(C\#) from Course);

11、查询至少有一门课与学号为“1001”的同学所学相同的同学的学号和姓名；

select S\#,Sname from Student,SC where Student.S\#=SC.S\# and C\# in select C\# from SC where S\#='1001';

12、查询至少学过学号为“001”同学所有一门课的其他同学学号和姓名；

select distinct SC.S\#,Sname

from Student,SC

where Student.S\#=SC.S\# and C\# in (select C\# from SC where S\#='001');

13、把“SC”表中“叶平”老师教的课的成绩都更改为此课程的平均成绩；

update SC set score=(select avg(SC\_2.score)

from SC SC\_2

where SC\_2.C\#=SC.C\# ) from Course,Teacher where Course.C\#=SC.C\# and Course.T\#=Teacher.T\# and Teacher.Tname='叶平');

14、查询和“1002”号的同学学习的课程完全相同的其他同学学号和姓名；

select S\# from SC where C\# in (select C\# from SC where S\#='1002')

group by S\# having count(\*)=(select count(\*) from SC where S\#='1002');

15、删除学习“叶平”老师课的SC表记录；

Delect SC

from course ,Teacher

where Course.C\#=SC.C\# and Course.T\#= Teacher.T\# and Tname='叶平';

16、向SC表中插入一些记录，这些记录要求符合以下条件：没有上过编号“003”课程的同学学号、2、

号课的平均成绩；

Insert SC select S\#,'002',(Select avg(score)

from SC where C\#='002') from Student where S\# not in (Select S\# from SC where C\#='002');

17、按平均成绩从高到低显示所有学生的“数据库”、“企业管理”、“英语”三门的课程成绩，按如下形式显示： 学生ID,,数据库,企业管理,英语,有效课程数,有效平均分

SELECT S\# as 学生ID

,(SELECT score FROM SC WHERE SC.S\#=t.S\# AND C\#='004') AS 数据库

,(SELECT score FROM SC WHERE SC.S\#=t.S\# AND C\#='001') AS 企业管理

,(SELECT score FROM SC WHERE SC.S\#=t.S\# AND C\#='006') AS 英语

,COUNT(\*) AS 有效课程数, AVG(t.score) AS 平均成绩

FROM SC AS t

GROUP BY S\#

ORDER BY avg(t.score)

18、查询各科成绩最高和最低的分：以如下形式显示：课程ID，最高分，最低分

SELECT L.C\# As 课程ID,L.score AS 最高分,R.score AS 最低分

FROM SC L ,SC AS R

WHERE L.C\# = R.C\# and

L.score = (SELECT MAX(IL.score)

FROM SC AS IL,Student AS IM

WHERE L.C\# = IL.C\# and IM.S\#=IL.S\#

GROUP BY IL.C\#)

AND

R.Score = (SELECT MIN(IR.score)

FROM SC AS IR

WHERE R.C\# = IR.C\#

GROUP BY IR.C\#

);

19、按各科平均成绩从低到高和及格率的百分数从高到低顺序

SELECT t.C\# AS 课程号,max(course.Cname)AS 课程名,isnull(AVG(score),0) AS 平均成绩

,100 \* SUM(CASE WHEN isnull(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(\*) AS 及格百分数

FROM SC T,Course

where t.C\#=course.C\#

GROUP BY t.C\#

ORDER BY 100 \* SUM(CASE WHEN isnull(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(\*) DESC

20、查询如下课程平均成绩和及格率的百分数(用"1行"显示): 企业管理（001），马克思（002），OO&UML （003），数据库（004）

SELECT SUM(CASE WHEN C\# ='001' THEN score ELSE 0 END)/SUM(CASE C\# WHEN '001' THEN 1ELSE0 END) AS 企业管理平均分

,100 \* SUM(CASE WHEN C\# = '001' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C\# = '001' THEN 1 ELSE 0 END) AS 企业管理及格百分数

,SUM(CASE WHEN C\# = '002' THEN score ELSE 0 END)/SUM(CASE C\# WHEN '002' THEN 1 ELSE0END) AS 马克思平均分

,100 \* SUM(CASE WHEN C\# = '002' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C\# = '002' THEN 1 ELSE 0 END) AS 马克思及格百分数

,SUM(CASE WHEN C\# = '003' THEN score ELSE 0 END)/SUM(CASE C\# WHEN '003' THEN 1 ELSE0END) AS UML平均分

,100 \* SUM(CASE WHEN C\# = '003' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C\# = '003' THEN 1 ELSE 0 END) AS UML及格百分数

,SUM(CASE WHEN C\# = '004' THEN score ELSE 0 END)/SUM(CASE C\# WHEN '004' THEN 1 ELSE0END) AS 数据库平均分

,100 \* SUM(CASE WHEN C\# = '004' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C\# = '004' THEN 1 ELSE 0 END) AS 数据库及格百分数

FROM SC

21、查询不同老师所教不同课程平均分从高到低显示

SELECT max(Z.T\#) AS 教师ID,MAX(Z.Tname) AS 教师姓名,C.C\# AS 课程ＩＤ,MAX(C.Cname) AS 课程名称,AVG(Score) AS 平均成绩

FROM SC AS T,Course AS C ,Teacher AS Z

where T.C\#=C.C\# and C.T\#=Z.T\#

GROUP BY C.C\#

ORDER BY AVG(Score) DESC

22、查询如下课程成绩第 3 名到第 6 名的学生成绩单：企业管理（001），马克思（002），UML （003），数据库（004）

\[学生ID\],\[学生姓名\],企业管理,马克思,UML,数据库,平均成绩

SELECT DISTINCT top 3

SC.S\# As 学生学号,

Student.Sname AS 学生姓名 ,

T1.score AS 企业管理,

T2.score AS 马克思,

T3.score AS UML,

T4.score AS 数据库,

ISNULL(T1.score,0) + ISNULL(T2.score,0) + ISNULL(T3.score,0) + ISNULL(T4.score,0) as 总分

FROM Student,SC LEFT JOIN SC AS T1

ON SC.S\# = T1.S\# AND T1.C\# = '001'

LEFT JOIN SC AS T2

ON SC.S\# = T2.S\# AND T2.C\# = '002'

LEFT JOIN SC AS T3

ON SC.S\# = T3.S\# AND T3.C\# = '003'

LEFT JOIN SC AS T4

ON SC.S\# = T4.S\# AND T4.C\# = '004'

WHERE student.S\#=SC.S\# and

ISNULL(T1.score,0) + ISNULL(T2.score,0) + ISNULL(T3.score,0) + ISNULL(T4.score,0)

NOT IN

(SELECT

DISTINCT

TOP 15 WITH TIES

ISNULL(T1.score,0) + ISNULL(T2.score,0) + ISNULL(T3.score,0) + ISNULL(T4.score,0)

FROM sc

LEFT JOIN sc AS T1

ON sc.S\# = T1.S\# AND T1.C\# = 'k1'

LEFT JOIN sc AS T2

ON sc.S\# = T2.S\# AND T2.C\# = 'k2'

LEFT JOIN sc AS T3

ON sc.S\# = T3.S\# AND T3.C\# = 'k3'

LEFT JOIN sc AS T4

ON sc.S\# = T4.S\# AND T4.C\# = 'k4'

ORDER BY ISNULL(T1.score,0) + ISNULL(T2.score,0) + ISNULL(T3.score,0) + ISNULL(T4.score,0) DESC);

23、统计列印各科成绩,各分数段人数:课程ID,课程名称,\[100-85\],\[85-70\],\[70-60\],\[ <60\]

SELECT SC.C\# as 课程ID, Cname as 课程名称

,SUM(CASE WHEN score BETWEEN 85 AND 100 THEN 1 ELSE 0 END) AS \[100 - 85\]

,SUM(CASE WHEN score BETWEEN 70 AND 85 THEN 1 ELSE 0 END) AS \[85 - 70\]

,SUM(CASE WHEN score BETWEEN 60 AND 70 THEN 1 ELSE 0 END) AS \[70 - 60\]

,SUM(CASE WHEN score < 60 THEN 1 ELSE 0 END) AS \[60 -\]

FROM SC,Course

where SC.C\#=Course.C\#

GROUP BY SC.C\#,Cname;

24、查询学生平均成绩及其名次

SELECT 1+(SELECT COUNT( distinct 平均成绩)

FROM (SELECT S\#,AVG(score) AS 平均成绩

FROM SC

GROUP BY S\#

) AS T1

WHERE 平均成绩 > T2.平均成绩) as 名次,

S\# as 学生学号,平均成绩

FROM (SELECT S\#,AVG(score) 平均成绩

FROM SC

GROUP BY S\#

) AS T2

ORDER BY 平均成绩 desc;

25、查询各科成绩前三名的记录![sad.gif][]不考虑成绩并列情况)

SELECT t1.S\# as 学生ID,t1.C\# as 课程ID,Score as 分数

FROM SC t1

WHERE score IN (SELECT TOP 3 score

FROM SC

WHERE t1.C\#= C\#

ORDER BY score DESC

)

ORDER BY t1.C\#;

26、查询每门课程被选修的学生数

select c\#,count(S\#) from sc group by C\#;

27、查询出只选修了一门课程的全部学生的学号和姓名

select SC.S\#,Student.Sname,count(C\#) AS 选课数

from SC ,Student

where SC.S\#=Student.S\# group by SC.S\# ,Student.Sname having count(C\#)=1;

28、查询男生、女生人数

Select count(Ssex) as 男生人数 from Student group by Ssex having Ssex='男';

Select count(Ssex) as 女生人数 from Student group by Ssex having Ssex='女'；

29、查询姓“张”的学生名单

SELECT Sname FROM Student WHERE Sname like '张%';

30、查询同名同性学生名单，并统计同名人数

select Sname,count(\*) from Student group by Sname having count(\*)>1;;

31、1981年出生的学生名单(注：Student表中Sage列的类型是datetime)

select Sname, CONVERT(char (11),DATEPART(year,Sage)) as age

from student

where CONVERT(char(11),DATEPART(year,Sage))='1981';

32、查询每门课程的平均成绩，结果按平均成绩升序排列，平均成绩相同时，按课程号降序排列

Select C\#,Avg(score) from SC group by C\# order by Avg(score),C\# DESC ;

33、查询平均成绩大于85的所有学生的学号、姓名和平均成绩

select Sname,SC.S\# ,avg(score)

from Student,SC

where Student.S\#=SC.S\# group by SC.S\#,Sname having    avg(score)>85;

34、查询课程名称为“数据库”，且分数低于60的学生姓名和分数

Select Sname,isnull(score,0)

from Student,SC,Course

where SC.S\#=Student.S\# and SC.C\#=Course.C\# and Course.Cname='数据库'and score <60;

35、查询所有学生的选课情况；

SELECT SC.S\#,SC.C\#,Sname,Cname

FROM SC,Student,Course

where SC.S\#=Student.S\# and SC.C\#=Course.C\# ;

36、查询任何一门课程成绩在70分以上的姓名、课程名称和分数；

SELECT distinct student.S\#,student.Sname,SC.C\#,SC.score

FROM student,Sc

WHERE SC.score>=70 AND SC.S\#=student.S\#;

37、查询不及格的课程，并按课程号从大到小排列

select c\# from sc where scor e <60 order by C\# ;

38、查询课程编号为003且课程成绩在80分以上的学生的学号和姓名；

select SC.S\#,Student.Sname from SC,Student where SC.S\#=Student.S\# and Score>80 and C\#='003';

39、求选了课程的学生人数

select count(\*) from sc;

40、查询选修“叶平”老师所授课程的学生中，成绩最高的学生姓名及其成绩

select Student.Sname,score

from Student,SC,Course C,Teacher

where Student.S\#=SC.S\# and SC.C\#=C.C\# and C.T\#=Teacher.T\# and Teacher.Tname='叶平' and SC.score=(select max(score)from SC where C\#=C.C\# );

41、查询各个课程及相应的选修人数

select count(\*) from sc group by C\#;

42、查询不同课程成绩相同的学生的学号、课程号、学生成绩

select distinct A.S\#,B.score from SC A ,SC B where A.Score=B.Score and A.C\# <>B.C\# ;

43、查询每门功成绩最好的前两名

SELECT t1.S\# as 学生ID,t1.C\# as 课程ID,Score as 分数

FROM SC t1

WHERE score IN (SELECT TOP 2 score

FROM SC

WHERE t1.C\#= C\#

ORDER BY score DESC

)

ORDER BY t1.C\#;

44、统计每门课程的学生选修人数（超过10人的课程才统计）。要求输出课程号和选修人数，查询结果按人数降序排列，查询结果按人数降序排列，若人数相同，按课程号升序排列

select C\# as 课程号,count(\*) as 人数

from sc

group by C\#

order by count(\*) desc,c\#

45、检索至少选修两门课程的学生学号

select S\#

from sc

group by s\#

having count(\*) > = 2

46、查询全部学生都选修的课程的课程号和课程名

select C\#,Cname

from Course

where C\# in (select c\# from sc group by c\#)

47、查询没学过“叶平”老师讲授的任一门课程的学生姓名

select Sname from Student where S\# not in (select S\# from Course,Teacher,SC where Course.T\#=Teacher.T\# and SC.C\#=course.C\# and Tname='叶平');

48、查询两门以上不及格课程的同学的学号及其平均成绩

select S\#,avg(isnull(score,0)) from SC where S\# in (select S\# from SC where score <60 group by S\# having count(\*)>2)group by S\#;

49、检索“004”课程分数小于60，按分数降序排列的同学学号

select S\# from SC where C\#='004'and score <60 order by score desc;

50、删除“002”同学的“001”课程的成绩

delete from Sc where S\#='001'and C\#='001';  
  
  
转载：[CSDN][]

转载于:https://www.cnblogs.com/leekenky/p/3390587.html

[sad.gif]: http://www.itmian4.com/static/image/smiley/default/sad.gif
[CSDN]: http://blog.csdn.net/zilinzhiyou/article/details/12163803

50个经典SQL题目

发表评论取消回复

还没有评论，来说两句吧...

相关阅读

相关 SQL经典50题（MySQL版）

相关常见的SQL面试题：经典50例

相关 50个常用SQL语句

相关常见 SQL 面试题：经典 50 例

相关 sql经典题目

相关几道经典的SQL笔试题目（有答案）

相关 SQL题目50道持续更新

相关 50道经典SQL练习题 MYSQL8.0实现

相关 50个经典SQL题目

相关 50 个经典 Spring 面试题