一个题目涉及到的50个Sql语句

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#,scorefrom SC where C#='001') a,(select s#,score
  from SC where C#='002') b
  where a.score>b.scoreand 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# havingavg(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 Studentleft Outer join SCon 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 Tnamelike '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 (selectdistinct( SC.S#)from SC,Course,Teacherwhere  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.Snamefrom Student,SCwhere Student.S#=SC.S#and SC.C#='001'andexists( 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 ,Teacherwhere SC.C#=Course.C#and Teacher.T#=Course.T#and Teacher.Tname='叶平'group by S# havingcount(SC.C#)=(selectcount(C#) from Course,Teacher where Teacher.T#=Course.T#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 S#,Snamefrom (select Student.S#,Student.Sname,score ,(select score from SC SC_2where SC_2.S#=Student.S#and SC_2.C#='002') score2
  from Student,SCwhere 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,SCwhere 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.Snamehaving count(C#) <(selectcount(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#,Snamefrom Student,SCwhere 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 SCset score=(selectavg(SC_2.score)
    from SC SC_2
    where SC_2.C#=SC.C# )from Course,Teacherwhere 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# havingcount(*)=(selectcount(*)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 SCselect S#,'002',(Selectavg(score)
    from SCwhere C#='002')from Studentwhere 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 scoreFROM SC WHERE SC.S#=t.S#AND C#='004')AS 数据库
        ,(SELECT scoreFROM SC WHERE SC.S#=t.S#AND C#='001')AS 企业管理
        ,(SELECT scoreFROM 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 SCAS 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.scoreAS 最高分,R.scoreAS 最低分
    FROM SC L ,SCAS R
    WHERE L.C#= R.C# and
        L.score = (SELECTMAX(IL.score)
                      FROM SCAS IL,StudentAS IM
                      WHERE L.C#= IL.C# and IM.S#=IL.S#
                      GROUPBY IL.C#)
        AND
        R.Score = (SELECTMIN(IR.score)
                      FROM SCAS IR
                      WHERE R.C#= IR.C#
                  GROUPBY 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(CASEWHEN  isnull(score,0)>=60THEN 1ELSE 0END)/COUNT(*)AS 及格百分数
    FROM SC T,Course
    where t.C#=course.C#
    GROUP BY t.C#
    ORDER BY 100* SUM(CASEWHEN  isnull(score,0)>=60THEN 1ELSE 0END)/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(CASEWHEN C# ='001'THEN score ELSE 0END)/SUM(CASE C# WHEN '001'THEN 1ELSE 0END) AS 企业管理平均分
        ,100* SUM(CASEWHEN C# = '001'AND score >= 60THEN 1ELSE 0END)/SUM(CASEWHEN C# = '001'THEN 1ELSE 0END) AS 企业管理及格百分数
        ,SUM(CASEWHEN C# = '002'THEN score ELSE 0END)/SUM(CASE C# WHEN '002'THEN 1ELSE 0END) AS 马克思平均分
        ,100* SUM(CASEWHEN C# = '002'AND score >= 60THEN 1ELSE 0END)/SUM(CASEWHEN C# = '002'THEN 1ELSE 0END) AS 马克思及格百分数
        ,SUM(CASEWHEN C# = '003'THEN score ELSE 0END)/SUM(CASE C# WHEN '003'THEN 1ELSE 0END) AS UML平均分
        ,100* SUM(CASEWHEN C# = '003'AND score >= 60THEN 1ELSE 0END)/SUM(CASEWHEN C# = '003'THEN 1ELSE 0END) AS UML及格百分数
        ,SUM(CASEWHEN C# = '004'THEN score ELSE 0END)/SUM(CASE C# WHEN '004'THEN 1ELSE 0END) AS 数据库平均分
        ,100* SUM(CASEWHEN C# = '004'AND score >= 60THEN 1ELSE 0END)/SUM(CASEWHEN C# = '004'THEN 1ELSE 0END) 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 SCAS T,CourseAS C ,TeacherAS 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'
            LEFTJOIN SC AS T2
                      ON SC.S#= T2.S# AND T2.C# ='002'
            LEFTJOIN SC AS T3
                      ON SC.S#= T3.S# AND T3.C# ='003'
            LEFTJOIN 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
            TOP15WITH TIES
            ISNULL(T1.score,0)+ ISNULL(T2.score,0)+ ISNULL(T3.score,0)+ ISNULL(T4.score,0)
      FROM sc
            LEFTJOIN sc AS T1
                      ON sc.S#= T1.S# AND T1.C# ='k1'
            LEFTJOIN sc AS T2
                      ON sc.S#= T2.S# AND T2.C# ='k2'
            LEFTJOIN sc AS T3
                      ON sc.S#= T3.S# AND T3.C# ='k3'
            LEFTJOIN sc AS T4
                      ON sc.S#= T4.S# AND T4.C# ='k4'
      ORDERBY 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, Cnameas 课程名称
        ,SUM(CASEWHEN score BETWEEN 85AND 100THEN 1ELSE 0END) AS [100 - 85]
        ,SUM(CASEWHEN score BETWEEN 70AND 85THEN 1ELSE 0END) AS [85 - 70]
        ,SUM(CASEWHEN score BETWEEN 60AND 70THEN 1ELSE 0END) AS [70 - 60]
        ,SUM(CASEWHEN score < 60THEN 1ELSE 0END) 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
      SELECT1+(SELECTCOUNT( distinct 平均成绩)
              FROM (SELECT S#,AVG(score)AS 平均成绩
                      FROM SC
                  GROUPBY 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
        GROUPBY S#
        ) 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.S#as 学生ID,t1.C#as 课程ID,Scoreas 分数
      FROM SC t1
      WHERE scoreIN (SELECTTOP 3 score
              FROM SC
              WHERE t1.C#= C#
            ORDERBY score DESC
              )
      ORDERBY 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.Snamehaving count(C#)=1;
28、查询男生、女生人数
    Select count(Ssex) as 男生人数 from Studentgroup by Ssex having Ssex='男';
    Select count(Ssex) as 女生人数 from Studentgroup by Ssex having Ssex='女'；
29、查询姓“张”的学生名单
    SELECT SnameFROM StudentWHERE Snamelike '张%';
30、查询同名同性学生名单，并统计同名人数
  select Sname,count(*)from Studentgroup 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>=70AND 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 <60order 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.Snamefrom SC,Studentwhere SC.S#=Student.S#and Score>80and 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=(selectmax(score)from SCwhere 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.scorefrom SC A  ,SC Bwhere A.Score=B.Scoreand 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,Scoreas 分数
      FROM SC t1
      WHERE scoreIN (SELECTTOP 2 score
              FROM SC
              WHERE t1.C#= C#
            ORDERBY score DESC
              )
      ORDERBY 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 Snamefrom Studentwhere S# not in (select S#from Course,Teacher,SCwhere 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 <60group by S# havingcount(*)>2)groupby 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 <60order 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';

 

 

//原文转自：http://blog.csdn.net/htl258/article/details/3945715