一道经典的数据库sql语句题目
SQL查询题目<!--列表视图页显示缩略图和文章摘要--><!--文章视图页显示全部内容--><!--如果有内容，显示内容-->
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SQL查询题目
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条件：
Student(Sno,Sname,Sage,Ssex) 学生表
Course(Cno,Cname,Tno) 课程表
SC(Sno,Cno,score) 成绩表（选课表）
Teacher(Tno,Tname) 教师表
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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.sno from (select sno,score from SC where cno='001') a,(select sno,score
? from SC where cno='002') b
? where a.score>b.score and a.sno=b.sno;
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2、查询平均成绩大于60分的同学的学号和平均成绩；
?select SNO,avg(score) ?from sc ?group by SNO having avg(score) >60;
3、查询所有同学的学号、姓名、选课数、总成绩；
?select Student.SNO,Student.Sname,count(SC.CNO),sum(score)
?from Student left Outer join SC on Student.SNO=SC.SNO
?group by Student.SNO,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.SNO,Student.Sname ?from Student?
?where SNO not in (select distinct(SC.SNO) from SC,Course,Teacher where? SC.CNO=Course.CNO and Teacher.Tno=Course.Tno 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.SNO,Student.Sname from Student,SC where Student.SNO=SC.SNO and SC.CNO='001'and exists( Select * from SC as SC_2 where SC_2.SNO=SC.SNO and SC_2.CNO='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 SNO,Sname
? from Student
? where SNO in (select SNO from SC ,Course ,Teacher where SC.CNO=Course.CNO and Teacher.TNO=Course.TNO and Teacher.Tname='叶平' group by SNO having count(SC.CNO)=(select count(CNO) from Course,Teacher? where Teacher.TNO=Course.TNO 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 SNO,Sname from (select Student.SNO,Student.Sname,score ,(select score from SC SC_2 where SC_2.SNO=Student.SNO and SC_2.CNO='002') score2
? from Student,SC where Student.SNO=SC.SNO and CNO='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 SNO,Sname
? from Student
? where SNO not in (select Student.SNO from Student,SC where S.SNO=SC.SNO and score>60);
10、查询没有学全所有课的同学的学号、姓名；? ?
select Student.SNO,Student.Sname
??? from Student,SC
??? where Student.SNO=SC.SNO group by? Student.SNO,Student.Sname having count(CNO) <(select count(CNO) from Course);
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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 SNO,Sname from Student,SC where Student.SNO=SC.SNO and CNO in select CNO from SC where SNO='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.SNO,Sname
??? from Student,SC
??? where Student.SNO=SC.SNO and CNO in (select CNO from SC where SNO='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.CNO=SC.CNO) from Course,Teacher where Course.CNO=SC.CNO and Course.TNO=Teacher.TNO 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 SNO from SC where CNO in (select CNO from SC where SNO='1002')
??? group by SNO having count(*)=(select count(*) from SC where SNO='1002');
???
15、删除学习“叶平”老师课的SC表记录；?
DelectSC
??? from course ,Teacher?
??? where Course.CNO=SC.CNO and Course.TNO= Teacher.TNO 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 SNO,'002',(Select avg(score)
??? from SC where CNO='002') from Student where SNO not in (Select SNO from SC where CNO='002');
17、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 SNO as 学生ID
??????? ,(SELECT score FROM SC WHERE SC.SNO=t.SNO AND CNO='004') AS 数据库
??????? ,(SELECT score FROM SC WHERE SC.SNO=t.SNO AND CNO='001') AS 企业管理
??????? ,(SELECT score FROM SC WHERE SC.SNO=t.SNO AND CNO='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 SNO
??? ORDER BY avg(t.score)?
18、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.CNO 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.CNO=course.CNO
??? GROUP BY t.CNO
??? ORDER BY 100 * SUM(CASE WHEN? isnull(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) DESC
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19、查询不同老师所教不同课程平均分从高到低显示
SELECT max(Z.TNO) AS 教师ID,MAX(Z.Tname) AS 教师姓名,C.CNO 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.CNO=C.CNO and C.TNO=Z.TNO
? GROUP BY C.CNO
? ORDER BY AVG(Score) DESC
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20、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.CNO 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.CNO=Course.CNO
??? GROUP BY SC.CNO,Cname;
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21、查询各科成绩前三名的记录:(不考虑成绩并列情况) ??
SELECT t1.SNO as 学生ID,t1.CNO as 课程ID,Score as 分数
????? FROM SC t1
????? WHERE score IN (SELECT TOP 3 score
????????????? FROM SC
????????????? WHERE t1.CNO= CNO
??????????? ORDER BY score DESC
?????????? ???)
????? ORDER BY t1.CNO;
22、查询每门课程被选修的学生数
select cno,count(SNO) from sc group by CNO;
23、查询出只选修了一门课程的全部学生的学号和姓名
select SC.SNO,Student.Sname,count(CNO) AS 选课数
? from SC ,Student
? where SC.SNO=Student.SNO group by SC.SNO ,Student.Sname having count(CNO)=1;
24、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'；
25、查询姓“张”的学生名单?
SELECT Sname FROM Student WHERE Sname like '张%';
26、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;
27、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';
28、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 CNO,Avg(score) from SC group by CNO order by Avg(score),CNO DESC ;
29、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.SNO ,avg(score)
??? from Student,SC
??? where Student.SNO=SC.SNO group by SC.SNO,Sname having ?avg(score)>85;
30、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.SNO=Student.SNO and SC.CNO=Course.CNO and? Course.Cname='数据库'and score <60;
31、查询所有学生的选课情况；
SELECT SC.SNO,SC.CNO,Sname,Cname
??? FROM SC,Student,Course
??? where SC.SNO=Student.SNO and SC.CNO=Course.CNO ;
32、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.SNO,student.Sname,SC.CNO,SC.score
??? FROM student,Sc
??? WHERE SC.score>=70 AND SC.SNO=student.SNO;
33、查询不及格的课程，并按课程号从大到小排列
select cno from sc where scor e <60 order by CNO ;
34、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.SNO,Student.Sname from SC,Student where SC.SNO=Student.SNO and Score>80 and CNO='003';
35、求选了课程的学生人数
select count(*) from sc;
36、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.SNO=SC.SNO and SC.CNO=C.CNO and C.TNO=Teacher.TNO and Teacher.Tname='叶平' and SC.score=(select max(score)from SC where CNO=C.CNO );
37、查询各个课程及相应的选修人数
select count(*) from sc group by CNO;
38、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.SNO,B.score from SC A? ,SC B where A.Score=B.Score and A.CNO <>B.CNO ;
39、查询每门功成绩最好的前两名
SELECT t1.SNO as 学生ID,t1.CNO as 课程ID,Score as 分数
??? ??FROM SC t1
????? WHERE score IN (SELECT TOP 2 score
????????????? FROM SC
????????????? WHERE t1.CNO= CNO ?
??????????? ORDER BY score DESC
????????????? )
????? ORDER BY t1.CNO;
40、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? CNO as 课程号,count(*) as 人数
??? from? sc?
??? group? by? CNO
??? order? by? count(*) desc,cno
41、检索至少选修两门课程的学生学号
select? SNO?
??? from? sc?
??? group? by? sno
??? having? count(*)? >? =? 2
42、查询全部学生都选修的课程的课程号和课程名
select? CNO,Cname?
??? from? Course?
??? where? CNO? in? (select? cno? from? sc group? by? cno)
43、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 SNO not in (select SNO from Course,Teacher,SC where Course.TNO=Teacher.TNO and SC.CNO=course.CNO and Tname='叶平');
44、查询两门以上不及格课程的同学的学号及其平均成绩
select SNO,avg(isnull(score,0)) from SC where SNO in (select SNO from SC where score <60 group by SNO having count(*)>2)group by SNO;
45、检索“004”课程分数小于60，按分数降序排列的同学学号
select SNO from SC where CNO='004'and score <60 order by score desc;
46、删除“002”同学的“001”课程的成绩
delete from Sc where SNO='001'and CNO='001';
