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1、表架構(gòu)Student(S#,Sname,Sage,Ssex) 學(xué)生表Course(C#,Cname,T#) 課程表SC(S#,C#,score) 成績表Teacher(T#,Tname) 教師表建表語句按 Ctrl+C 復(fù)制代碼按 Ctrl+C 復(fù)制代碼插入測試數(shù)據(jù)語句按 Ctrl+C 復(fù)制代碼按 Ctrl+C 復(fù)制代碼問題問題: 1、查詢“001”課程比“002”課程成績高的所有學(xué)生的學(xué)號; select a.S# from (select s#,score from SC where C#=001) a,(select s#,score from SC where C#=002) b wh

2、ere a.scoreb.score and a.s#=b.s#; 2、查詢平均成績大于60分的同學(xué)的學(xué)號和平均成績; select S#,avg(score) from sc group by S# having avg(score) 60; 3、查詢所有同學(xué)的學(xué)號、姓名、選課數(shù)、總成績; 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、查詢姓“李”的老師的個數(shù); sel

3、ect count(distinct(Tname) from Teacher where Tname like 李%; 5、查詢沒學(xué)過“葉平”老師課的同學(xué)的學(xué)號、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=葉平); 6、查詢學(xué)過“001”并且也學(xué)過編號“002”課程的同學(xué)的學(xué)號、姓名;

4、select Student.S#,Student.Sname from Student,SC where Student.S#=SC.S# and SC.C#=001and exists( Select * from SC as SC_2 where SC_2.S#=SC.S# and SC_2.C#=002); 7、查詢學(xué)過“葉平”老師所教的所有課的同學(xué)的學(xué)號、姓名; select S#,Sname from Student where S# in (select S# from SC ,Course ,Teacher where SC.C#=Course.C# and Teacher.T

5、#=Course.T# and Teacher.Tname=葉平 group by S# having count(SC.C#)=(select count(C#) from Course,Teacher where Teacher.T#=Course.T# and Tname=葉平); 8、查詢課程編號“002”的成績比課程編號“001”課程低的所有同學(xué)的學(xué)號、姓名; Select S#,Sname from (select Student.S#,Student.Sname,score ,(select score from SC SC_2 where SC_2.S#=Student.S#

6、and SC_2.C#=002) score2 from Student,SC where Student.S#=SC.S# and C#=001) S_2 where score2 60); 10、查詢沒有學(xué)全所有課的同學(xué)的學(xué)號、姓名; select Student.S#,Student.Sname from Student,SC where Student.S#=SC.S# group by Student.S#,Student.Sname having count(C#) =60 THEN 1 ELSE 0 END)/COUNT(*) AS 及格百分?jǐn)?shù) FROM SC T,Course

7、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、查詢?nèi)缦抡n程平均成績和及格率的百分?jǐn)?shù)(用1行顯示): 企業(yè)管理(001),馬克思(002),OO&UML (003),數(shù)據(jù)庫(004) SELECT SUM(CASE WHEN C# =001 THEN score ELSE 0 END)/SUM(CASE C# WHEN 001 THEN 1 ELSE 0 END) AS 企業(yè)管理平均分 ,100 * SUM

8、(CASE WHEN C# = 001 AND score = 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C# = 001 THEN 1 ELSE 0 END) AS 企業(yè)管理及格百分?jǐn)?shù) ,SUM(CASE WHEN C# = 002 THEN score ELSE 0 END)/SUM(CASE C# WHEN 002 THEN 1 ELSE 0 END) AS 馬克思平均分 ,100 * SUM(CASE WHEN C# = 002 AND score = 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN C# = 002 THEN 1

9、ELSE 0 END) AS 馬克思及格百分?jǐn)?shù) ,SUM(CASE WHEN C# = 003 THEN score ELSE 0 END)/SUM(CASE C# WHEN 003 THEN 1 ELSE 0 END) 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?jǐn)?shù) ,SUM(CASE WHEN C# = 004 THEN score ELSE 0 END)/SUM(CASE C# WH

10、EN 004 THEN 1 ELSE 0 END) AS 數(shù)據(jù)庫平均分 ,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 數(shù)據(jù)庫及格百分?jǐn)?shù) FROM SC 21、查詢不同老師所教不同課程平均分從高到低顯示 SELECT max(Z.T#) AS 教師ID,MAX(Z.Tname) AS 教師姓名,C.C# AS 課程,MAX(C.Cname) AS 課程名稱,AVG(Score) AS 平均成績 FROM SC AS T,Cou

11、rse 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、查詢?nèi)缦抡n程成績第 3 名到第 6 名的學(xué)生成績單:企業(yè)管理(001),馬克思(002),UML (003),數(shù)據(jù)庫(004) 學(xué)生ID,學(xué)生姓名,企業(yè)管理,馬克思,UML,數(shù)據(jù)庫,平均成績 SELECT DISTINCT top 3 SC.S# As 學(xué)生學(xué)號, Student.Sname AS 學(xué)生姓名 , T1.score AS 企業(yè)管理, T2.score AS 馬克思, T3.score AS U

12、ML, T4.score AS 數(shù)據(jù)庫, ISNULL(T1.score,0) + ISNULL(T2.score,0) + ISNULL(T3.score,0) + ISNULL(T4.score,0) as 總分 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

13、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#

14、 = 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、統(tǒng)計列印各科成績,各分?jǐn)?shù)段人數(shù):課程ID,課

15、程名稱,100-85,85-70,70-60, 60 SELECT SC.C# as 課程ID, Cname as 課程名稱 ,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 T2.平均成績

16、) as 名次, S# as 學(xué)生學(xué)號,平均成績 FROM (SELECT S#,AVG(score) 平均成績 FROM SC GROUP BY S# ) AS T2 ORDER BY 平均成績 desc; 25、查詢各科成績前三名的記錄:(不考慮成績并列情況) SELECT t1.S# as 學(xué)生ID,t1.C# as 課程ID,Score as 分?jǐn)?shù) 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、查詢每門課程被選修

17、的學(xué)生數(shù) select c#,count(S#) from sc group by C#; 27、查詢出只選修了一門課程的全部學(xué)生的學(xué)號和姓名 select SC.S#,Student.Sname,count(C#) AS 選課數(shù) from SC ,Student where SC.S#=Student.S# group by SC.S# ,Student.Sname having count(C#)=1; 28、查詢男生、女生人數(shù) Select count(Ssex) as 男生人數(shù) from Student group by Ssex having Ssex=男; Select count

18、(Ssex) as 女生人數(shù) from Student group by Ssex having Ssex=女; 29、查詢姓“張”的學(xué)生名單 SELECT Sname FROM Student WHERE Sname like 張%; 30、查詢同名同性學(xué)生名單,并統(tǒng)計同名人數(shù) select Sname,count(*) from Student group by Sname having count(*)1; 31、1981年出生的學(xué)生名單(注:Student表中Sage列的類型是datetime) select Sname, CONVERT(char (11),DATEPART(year

19、,Sage) as age from student where CONVERT(char(11),DATEPART(year,Sage)=1981; 32、查詢每門課程的平均成績,結(jié)果按平均成績升序排列,平均成績相同時,按課程號降序排列 Select C#,Avg(score) from SC group by C# order by Avg(score),C# DESC ; 33、查詢平均成績大于85的所有學(xué)生的學(xué)號、姓名和平均成績 select Sname,SC.S# ,avg(score) from Student,SC where Student.S#=SC.S# group by

20、SC.S#,Sname having avg(score)85; 34、查詢課程名稱為“數(shù)據(jù)庫”,且分?jǐn)?shù)低于60的學(xué)生姓名和分?jǐn)?shù) Select Sname,isnull(score,0) from Student,SC,Course where SC.S#=Student.S# and SC.C#=Course.C# and Course.Cname=數(shù)據(jù)庫and score =70 AND SC.S#=student.S#; 37、查詢不及格的課程,并按課程號從大到小排列 select c# from sc where scor e 80 and C#=003; 39、求選了課程的學(xué)生人數(shù)

21、select count(*) from sc; 40、查詢選修“葉平”老師所授課程的學(xué)生中,成績最高的學(xué)生姓名及其成績 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=葉平 and SC.score=(select max(score)from SC where C#=C.C# ); 41、查詢各個課程及相應(yīng)的選修人數(shù) select count(*) from sc gr

22、oup by C#; 42、查詢不同課程成績相同的學(xué)生的學(xué)號、課程號、學(xué)生成績 select distinct A.S#,B.score from SC A ,SC B where A.Score=B.Score and A.C# B.C# ; 43、查詢每門功成績最好的前兩名 SELECT t1.S# as 學(xué)生ID,t1.C# as 課程ID,Score as 分?jǐn)?shù) 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、統(tǒng)計

23、每門課程的學(xué)生選修人數(shù)(超過10人的課程才統(tǒng)計)。要求輸出課程號和選修人數(shù),查詢結(jié)果按人數(shù)降序排列,查詢結(jié)果按人數(shù)降序排列,若人數(shù)相同,按課程號升序排列 select C# as 課程號,count(*) as 人數(shù) from sc group by C# order by count(*) desc,c# 45、檢索至少選修兩門課程的學(xué)生學(xué)號 select S# from sc group by s# having count(*) = 2 46、查詢?nèi)繉W(xué)生都選修的課程的課程號和課程名 select C#,Cname from Course where C# in (select c# f

24、rom sc group by c#) 47、查詢沒學(xué)過“葉平”老師講授的任一門課程的學(xué)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=葉平); 48、查詢兩門以上不及格課程的同學(xué)的學(xué)號及其平均成績 select S#,avg(isnull(score,0) from SC where S# in (select S# from SC where score 2)grou

25、p by S#; 49、檢索“004”課程分?jǐn)?shù)小于60,按分?jǐn)?shù)降序排列的同學(xué)學(xué)號 select S# from SC where C#=004and score 53. 查詢借閱了水滸一書的讀者,輸出姓名及班級-實現(xiàn)代碼:SELECT * FROM CARD cWHERE EXISTS( SELECT * FROM BORROW a,BOOKS b WHERE a.BNO=b.BNO AND b.BNAME=N水滸 AND a.CNO=c.CNO) 4. 查詢過期未還圖書,輸出借閱者(卡號)、書號及還書日期-實現(xiàn)代碼:SELECT * FROM BORROW WHERE RDATE0INSER

26、T BORROW_SAVE SELECT i.*FROM INSERTED i,BOOKS bWHERE i.BNO=b.BNO AND b.BNAME=N數(shù)據(jù)庫技術(shù)及應(yīng)用 12. 建立一個視圖,顯示力01班學(xué)生的借書信息(只要求顯示姓名和書名)-實現(xiàn)代碼:CREATE VIEW V_VIEWASSELECT a.NAME,b.BNAMEFROM BORROW ab,CARD a,BOOKS bWHERE ab.CNO=a.CNO AND ab.BNO=b.BNO AND a.CLASS=N力0113. 查詢當(dāng)前同時借有計算方法和組合數(shù)學(xué)兩本書的讀者,輸出其借書卡號,并按卡號升序排序輸出-實現(xiàn)

27、代碼:SELECT a.CNOFROM BORROW a,BOOKS bWHERE a.BNO=b.BNO AND b.BNAME IN(N計算方法,N組合數(shù)學(xué))GROUP BY a.CNOHAVING COUNT(*)=2ORDER BY a.CNO DESC 14. 假定在建BOOKS表時沒有定義主碼,寫出為BOOKS表追加定義主碼的語句-實現(xiàn)代碼:ALTER TABLE BOOKS ADD PRIMARY KEY(BNO) 15.1 將NAME最大列寬增加到10個字符(假定原為6個字符)-實現(xiàn)代碼:ALTER TABLE CARD ALTER COLUMN NAME varchar(10

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