最全SQL笔试题

如下四个数据表

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.SID from (select Sid,score from SC where CID='001') a,(select Sid,score from SC where CID='002') b where a.score>b.score and a.Sid=b.Sid; 

2、查询平均成绩大于60分的同学的学号和平均成绩

select SID,avg(score) from sc group by SID having avg(score) > 60; 

3、查询所有同学的学号、姓名、选课数、总成绩

select Student.SID,Student.Sname,count(SC.CID),sum(score) from Student left Outer join SC on Student.SID=SC.SID group by Student.SID,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.SID,Student.Sname from Student where SID not in (select distinct(SC.SID) from SC,Course,Teacher where SC.CID=Course.CID and Teacher.TID=Course.TID 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.SID,Student.Sname from Student,SC where Student.SID=SC.SID and SC.CID='001' and exists( select * from SC as SC_2 where SC_2.SID=SC.SID and SC_2.CID='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 SID,Sname from Student where SID in (select SID from SC ,Course ,Teacher where SC.CID=Course.CID and Teacher.TID=Course.TID and Teacher.Tname='叶平' group by SID having count(SC.CID)=(select count(CID) from Course,Teacher where Teacher.TID=Course.TID and Tname='叶平')); 

8、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

Select SID,Sname from (select Student.SID,Student.Sname,score ,(select score from SC SC_2 where SC_2.SID=Student.SID and SC_2.CID='002') score2 from Student,SC where Student.SID=SC.SID and CID='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 SID,Sname from Student where SID not in (select Student.SID from Student,SC where S.SID=SC.SID and score>60); 

10、查询没有学全所有课的同学的学号、姓名

select Student.SID,Student.Sname from Student,SC where Student.SID=SC.SID group by Student.SID,Student.Sname having count(CID) <(select count(CID) 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 SID,Sname from Student,SC where Student.SID=SC.SID and CID in select CID from SC where SID='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.SID,Sname from Student,SC where Student.SID=SC.SID and CID in (select CID from SC where SID='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.CID=SC.CID ) from Course,Teacher where Course.CID=SC.CID and Course.TID=Teacher.TID 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 SID from SC where CID in (select CID from SC where SID='1002') group by SID having count(*)=(select count(*) from SC where SID='1002'); 

15、删除学习“叶平”老师课的SC表记录

Delect SC from course ,Teacher where Course.CID=SC.CID and Course.TID= Teacher.TID 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、002号课的平均成绩

Insert SC select SID,'002',(Select avg(score) from SC where CID='002') from Student where SID not in (Select SID from SC where CID='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 SID as 学生ID ,(SELECT score FROM SC WHERE SC.SID=t.SID AND CID='004') AS 数据库 ,(SELECT score FROM SC WHERE SC.SID=t.SID AND CID='001') AS 企业管理 ,(SELECT score FROM SC WHERE SC.SID=t.SID AND CID='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 SID 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.CID As 课程ID,L.score AS 最高分,R.score AS 最低分 FROM SC L ,SC AS R WHERE L.CID = R.CID and L.score = (SELECT MAX(IL.score) FROM SC AS IL,Student AS IM WHERE L.CID = IL.CID and IM.SID=IL.SID GROUP BY IL.CID) AND R.Score = (SELECT MIN(IR.score) FROM SC AS IR WHERE R.CID = IR.CID GROUP BY IR.CID); 

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.CID 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.CID=course.CID GROUP BY t.CID 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 CID ='001' THEN score ELSE 0 END)/SUM(CASE CID WHEN '001' THEN 1 ELSE 0 END) AS 企业管理平均分 ,100 * SUM(CASE WHEN CID = '001' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN CID = '001' THEN 1 ELSE 0 END) AS 企业管理及格百分数 ,SUM(CASE WHEN CID = '002' THEN score ELSE 0 END)/SUM(CASE CID WHEN '002' THEN 1 ELSE 0 END) AS 马克思平均分 ,100 * SUM(CASE WHEN CID = '002' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN CID = '002' THEN 1 ELSE 0 END) AS 马克思及格百分数 ,SUM(CASE WHEN CID = '003' THEN score ELSE 0 END)/SUM(CASE CID WHEN '003' THEN 1 ELSE 0 END) AS UML平均分 ,100 * SUM(CASE WHEN CID = '003' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN CID = '003' THEN 1 ELSE 0 END) AS UML及格百分数 ,SUM(CASE WHEN CID = '004' THEN score ELSE 0 END)/SUM(CASE CID WHEN '004' THEN 1 ELSE 0 END) AS 数据库平均分 ,100 * SUM(CASE WHEN CID = '004' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN CID = '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.TID) AS 教师ID,MAX(Z.Tname) AS 教师姓名,C.CID 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.CID=C.CID and C.TID=Z.TID GROUP BY C.CID 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.SID 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.SID = T1.SID AND T1.CID = '001' LEFT JOIN SC AS T2 ON SC.SID = T2.SID AND T2.CID = '002' LEFT JOIN SC AS T3 ON SC.SID = T3.SID AND T3.CID = '003' LEFT JOIN SC AS T4 ON SC.SID = T4.SID AND T4.CID = '004' WHERE student.SID=SC.SID 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.SID = T1.SID AND T1.CID = 'k1' LEFT JOIN sc AS T2 ON sc.SID = T2.SID AND T2.CID = 'k2' LEFT JOIN sc AS T3 ON sc.SID = T3.SID AND T3.CID = 'k3' LEFT JOIN sc AS T4 ON sc.SID = T4.SID AND T4.CID = '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.CID 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.CID=Course.CID GROUP BY SC.CID,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 SID,AVG(score) AS 平均成绩 FROM SC GROUP BY SID ) AS T1 WHERE 平均成绩> T2.平均成绩) as 名次, SID as 学生学号,平均成绩 FROM (SELECT SID,AVG(score) 平均成绩 FROM SC GROUP BY SID ) AS T2 ORDER BY 平均成绩desc; 

25、查询各科成绩前三名的记录:(不考虑成绩并列情况)

SELECT t1.SID as 学生ID,t1.CID as 课程ID,Score as 分数 FROM SC t1 WHERE score IN (SELECT TOP 3 score FROM SC WHERE t1.CID= CID ORDER BY score DESC ) ORDER BY t1.CID; 

26、查询每门课程被选修的学生数

select Cid,count(SID) from sc group by CID; 

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.SID,Student.Sname,count(CID) AS 选课数 from SC ,Student where SC.SID=Student.SID group by SC.SID ,Student.Sname having count(CID)=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 CID,Avg(score) from SC group by CID order by Avg(score),CID 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.SID ,avg(score) from Student,SC where Student.SID=SC.SID group by SC.SID,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.SID=Student.SID and SC.CID=Course.CID and Course.Cname='数据库'and score <60; 

35、查询所有学生的选课情况；

SELECT SC.SID,SC.CID,Sname,Cname FROM SC,Student,Course where SC.SID=Student.SID and SC.CID=Course.CID ; 

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.SID,student.Sname,SC.CID,SC.score FROM student,Sc WHERE SC.score>=70 AND SC.SID=student.SID; 

37、查询不及格的课程，并按课程号从大到小排列

select Cid from sc where scor e <60 order by CID ; 

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.SID,Student.Sname from SC,Student where SC.SID=Student.SID and Score>80 and CID='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,CourseC,Teacher where Student.SID=SC.SID and SC.CID=C.CID and C.TID=Teacher.TID and Teacher.Tname='叶平' and SC.score=(select max(score)from SC where CID=C.CID ); 

41、查询各个课程及相应的选修人数

select count(*) from sc group by CID; 

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.SID,B.score from SC A ,SC B where A.Score=B.Score and A.CID <>B.CID ; 

43、查询每门功成绩最好的前两名

SELECT t1.SID as 学生ID,t1.CID as 课程ID,Score as 分数 FROM SC t1 WHERE score IN (SELECT TOP 2 score FROM SC WHERE t1.CID= CID ORDER BY score DESC ) ORDER BY t1.CID; 

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 CID as 课程号,count(*) as 人数 from sc group by CID order by count(*) desc,Cid 

45、检索至少选修两门课程的学生学号

select SID from sc group by Sid 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 CID,Cname from Course where CID in (select Cid from sc group by Cid) 

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 SID not in (select SID from Course,Teacher,SC where Course.TID=Teacher.TID and SC.CID=course.CID 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 SID,avg(isnull(score,0)) from SC where SID in (select SID from SC where score <60 group by SID having count(*)>2)group by SID;