SQL面试题及答案
Student(S#,Sname,Sage,Ssex) 學(xué)生表 ? ? ? S#：學(xué)號(hào)；Sname：學(xué)生姓名；Sage：學(xué)生年齡；Ssex：學(xué)生性別
Course(C#,Cname,T#) 課程表 ? ? ? ? ? ? ? ? ? ?C#,課程編號(hào)；Cname：課程名字；T#：教師編號(hào)
SC(S#,C#,score) 成績表 ? ? ? ? ? ? ? ? ? ? ? ? ? ? S#：學(xué)號(hào)；C#,課程編號(hào)；score：成績
Teacher(T#,Tname) 教師表 ? ? ? ? ? ? ? ? ? ? ? ?T#：教師編號(hào)； Tname：教師名字
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(hào)；?
? 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、查詢平均成績大于60分的同學(xué)的學(xué)號(hào)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(hào)、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(gè)數(shù)；?
? select 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(hào)、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(hào)“002”課程的同學(xué)的學(xué)號(hào)、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、查詢學(xué)過“葉平”老師所教的所有課的同學(xué)的學(xué)號(hào)、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='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(hào)“002”的成績比課程編號(hào)“001”課程低的所有同學(xué)的學(xué)號(hào)、姓名；?
? 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、查詢所有課程成績小于60分的同學(xué)的學(xué)號(hào)、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、查詢沒有學(xué)全所有課的同學(xué)的學(xué)號(hào)、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、查詢至少有一門課與學(xué)號(hào)為“1001”的同學(xué)所學(xué)相同的同學(xué)的學(xué)號(hào)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、查詢至少學(xué)過學(xué)號(hào)為“001”同學(xué)所有一門課的其他同學(xué)學(xué)號(hào)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“葉平”老師教的課的成績都更改為此課程的平均成績；?
? ? 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='葉平');?
14、查詢和“1002”號(hào)的同學(xué)學(xué)習(xí)的課程完全相同的其他同學(xué)學(xué)號(hào)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、刪除學(xué)習(xí)“葉平”老師課的SC表記錄；?
? ? Delect SC?
? ? from course ,Teacher ?
? ? where Course.C#=SC.C# and Course.T#= Teacher.T# and Tname='葉平';?
16、向SC表中插入一些記錄，這些記錄要求符合以下條件：沒有上過編號(hào)“003”課程的同學(xué)學(xué)號(hào)、2、?
? ? 號(hào)課的平均成績；?
? ? 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、按平均成績從高到低顯示所有學(xué)生的“數(shù)據(jù)庫”、“企業(yè)管理”、“英語”三門的課程成績，按如下形式顯示： 學(xué)生ID,,數(shù)據(jù)庫,企業(yè)管理,英語,有效課程數(shù),有效平均分?
? ? SELECT S# as 學(xué)生ID?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='004') AS 數(shù)據(jù)庫?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='001') AS 企業(yè)管理?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='006') AS 英語?
? ? ? ? ,COUNT(*) AS 有效課程數(shù), AVG(t.score) AS 平均成績?
? ? FROM SC AS t?
? ? GROUP BY S#?
? ? ORDER BY avg(t.score) ?
18、查詢各科成績最高和最低的分：以如下形式顯示：課程ID，最高分，最低分?
? ? SELECT L.C# As 課程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、按各科平均成績從低到高和及格率的百分?jǐn)?shù)從高到低順序?
? ? SELECT t.C# AS 課程號(hào),max(course.Cname)AS 課程名,isnull(AVG(score),0) AS 平均成績?
? ? ? ? ,100 * SUM(CASE WHEN ?isnull(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) AS 及格百分?jǐn)?shù)?
? ? 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(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 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# WHEN '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ＩＤ,MAX(C.Cname) AS 課程名稱,AVG(Score) AS 平均成績?
? ? 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(hào),?
? ? ? ? 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 UML,?
? ? ? 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?
? ? ? ? ? ? ? ? ? ? ? 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、統(tǒng)計(jì)列印各科成績,各分?jǐn)?shù)段人數(shù):課程ID,課程名稱,[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 < 60 THEN 1 ELSE 0 END) AS [60 -]?
? ? FROM SC,Course?
? ? where SC.C#=Course.C#?
? ? GROUP BY SC.C#,Cname;?
24、查詢學(xué)生平均成績及其名次?
? ? ? SELECT 1+(SELECT COUNT( distinct 平均成績)?
? ? ? ? ? ? ? FROM (SELECT S#,AVG(score) AS 平均成績?
? ? ? ? ? ? ? ? ? ? ? FROM SC?
? ? ? ? ? ? ? ? ? GROUP BY S#?
? ? ? ? ? ? ? ? ? ) AS T1?
? ? ? ? ? ? WHERE 平均成績 > T2.平均成績) as 名次,?
? ? ? S# as 學(xué)生學(xué)號(hào),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(hào)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(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(jì)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,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(shí)，按課程號(hào)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(hào)、姓名和平均成績?
? ? 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 <60;?
35、查詢所有學(xué)生的選課情況；?
? ? SELECT SC.S#,SC.C#,Sname,Cname?
? ? FROM SC,Student,Course?
? ? where SC.S#=Student.S# and SC.C#=Course.C# ;?
36、查詢?nèi)魏我婚T課程成績在70分以上的姓名、課程名稱和分?jǐn)?shù)；?
? ? SELECT ?distinct student.S#,student.Sname,SC.C#,SC.score?
? ? FROM student,Sc?
? ? WHERE SC.score>=70 AND SC.S#=student.S#;?
37、查詢不及格的課程，并按課程號(hào)從大到小排列?
? ? select c# from sc where scor e <60 order by C# ;?
38、查詢課程編號(hào)為003且課程成績在80分以上的學(xué)生的學(xué)號(hào)和姓名；?
? ? select SC.S#,Student.Sname from SC,Student where SC.S#=Student.S# and Score>80 and C#='003';?
39、求選了課程的學(xué)生人數(shù)?
? ? 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(gè)課程及相應(yīng)的選修人數(shù)?
? ? select count(*) from sc group by C#;?
42、查詢不同課程成績相同的學(xué)生的學(xué)號(hào)、課程號(hào)、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(jì)每門課程的學(xué)生選修人數(shù)（超過10人的課程才統(tǒng)計(jì)）。要求輸出課程號(hào)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(hào)升序排列 ?
? ? select ?C# as 課程號(hào),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(hào)?
? ? 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(hào)和課程名?
? ? select ?C#,Cname ?
? ? from ?Course ?
? ? where ?C# ?in ?(select ?c# ?from ?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(hào)及其平均成績?
? ? 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、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(hào)?
? ? select S# from SC where C#='004'and score <60 order by score desc;?
50、刪除“002”同學(xué)的“001”課程的成績?
delete from Sc where S#='002'and C#='001';?
-- Create table create table DB_IMP_SC (S# NUMBER not null,C# NUMBER,SCORE VARCHAR2(10) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_SCis ' 成績表 '; -- Add comments to the columns comment on column DB_IMP_SC.S#is '學(xué)號(hào)'; comment on column DB_IMP_SC.C#is '課程編號(hào)'; comment on column DB_IMP_SC.SCOREis '成績';
-- Create table create table DB_IMP_STUDENT (S# NUMBER not null,SNAME VARCHAR2(12),SAGE VARCHAR2(3),SSEX VARCHAR2(2) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_STUDENTis ' 學(xué)生表'; -- Add comments to the columns comment on column DB_IMP_STUDENT.S#is '學(xué)號(hào)'; comment on column DB_IMP_STUDENT.SNAMEis '學(xué)生姓名'; comment on column DB_IMP_STUDENT.SAGEis '學(xué)生年齡'; comment on column DB_IMP_STUDENT.SSEXis '學(xué)生性別 ';
-- Create table create table DB_IMP_TEACHER (T# NUMBER not null,TNAME VARCHAR2(12) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_TEACHERis '教師表 '; -- Add comments to the columns comment on column DB_IMP_TEACHER.T#is '教師編號(hào)'; comment on column DB_IMP_TEACHER.TNAMEis '教師名字';
經(jīng)典！
Course(C#,Cname,T#) 課程表 ? ? ? ? ? ? ? ? ? ?C#,課程編號(hào)；Cname：課程名字；T#：教師編號(hào)
SC(S#,C#,score) 成績表 ? ? ? ? ? ? ? ? ? ? ? ? ? ? S#：學(xué)號(hào)；C#,課程編號(hào)；score：成績
Teacher(T#,Tname) 教師表 ? ? ? ? ? ? ? ? ? ? ? ?T#：教師編號(hào)； Tname：教師名字
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(hào)；?
? 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、查詢平均成績大于60分的同學(xué)的學(xué)號(hào)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(hào)、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(gè)數(shù)；?
? select 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(hào)、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(hào)“002”課程的同學(xué)的學(xué)號(hào)、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、查詢學(xué)過“葉平”老師所教的所有課的同學(xué)的學(xué)號(hào)、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='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(hào)“002”的成績比課程編號(hào)“001”課程低的所有同學(xué)的學(xué)號(hào)、姓名；?
? 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、查詢所有課程成績小于60分的同學(xué)的學(xué)號(hào)、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、查詢沒有學(xué)全所有課的同學(xué)的學(xué)號(hào)、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、查詢至少有一門課與學(xué)號(hào)為“1001”的同學(xué)所學(xué)相同的同學(xué)的學(xué)號(hào)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、查詢至少學(xué)過學(xué)號(hào)為“001”同學(xué)所有一門課的其他同學(xué)學(xué)號(hào)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“葉平”老師教的課的成績都更改為此課程的平均成績；?
? ? 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='葉平');?
14、查詢和“1002”號(hào)的同學(xué)學(xué)習(xí)的課程完全相同的其他同學(xué)學(xué)號(hào)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、刪除學(xué)習(xí)“葉平”老師課的SC表記錄；?
? ? Delect SC?
? ? from course ,Teacher ?
? ? where Course.C#=SC.C# and Course.T#= Teacher.T# and Tname='葉平';?
16、向SC表中插入一些記錄，這些記錄要求符合以下條件：沒有上過編號(hào)“003”課程的同學(xué)學(xué)號(hào)、2、?
? ? 號(hào)課的平均成績；?
? ? 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、按平均成績從高到低顯示所有學(xué)生的“數(shù)據(jù)庫”、“企業(yè)管理”、“英語”三門的課程成績，按如下形式顯示： 學(xué)生ID,,數(shù)據(jù)庫,企業(yè)管理,英語,有效課程數(shù),有效平均分?
? ? SELECT S# as 學(xué)生ID?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='004') AS 數(shù)據(jù)庫?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='001') AS 企業(yè)管理?
? ? ? ? ,(SELECT score FROM SC WHERE SC.S#=t.S# AND C#='006') AS 英語?
? ? ? ? ,COUNT(*) AS 有效課程數(shù), AVG(t.score) AS 平均成績?
? ? FROM SC AS t?
? ? GROUP BY S#?
? ? ORDER BY avg(t.score) ?
18、查詢各科成績最高和最低的分：以如下形式顯示：課程ID，最高分，最低分?
? ? SELECT L.C# As 課程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、按各科平均成績從低到高和及格率的百分?jǐn)?shù)從高到低順序?
? ? SELECT t.C# AS 課程號(hào),max(course.Cname)AS 課程名,isnull(AVG(score),0) AS 平均成績?
? ? ? ? ,100 * SUM(CASE WHEN ?isnull(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) AS 及格百分?jǐn)?shù)?
? ? 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(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 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# WHEN '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ＩＤ,MAX(C.Cname) AS 課程名稱,AVG(Score) AS 平均成績?
? ? 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(hào),?
? ? ? ? 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 UML,?
? ? ? 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?
? ? ? ? ? ? ? ? ? ? ? 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、統(tǒng)計(jì)列印各科成績,各分?jǐn)?shù)段人數(shù):課程ID,課程名稱,[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 < 60 THEN 1 ELSE 0 END) AS [60 -]?
? ? FROM SC,Course?
? ? where SC.C#=Course.C#?
? ? GROUP BY SC.C#,Cname;?
24、查詢學(xué)生平均成績及其名次?
? ? ? SELECT 1+(SELECT COUNT( distinct 平均成績)?
? ? ? ? ? ? ? FROM (SELECT S#,AVG(score) AS 平均成績?
? ? ? ? ? ? ? ? ? ? ? FROM SC?
? ? ? ? ? ? ? ? ? GROUP BY S#?
? ? ? ? ? ? ? ? ? ) AS T1?
? ? ? ? ? ? WHERE 平均成績 > T2.平均成績) as 名次,?
? ? ? S# as 學(xué)生學(xué)號(hào),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(hào)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(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(jì)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,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(shí)，按課程號(hào)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(hào)、姓名和平均成績?
? ? 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 <60;?
35、查詢所有學(xué)生的選課情況；?
? ? SELECT SC.S#,SC.C#,Sname,Cname?
? ? FROM SC,Student,Course?
? ? where SC.S#=Student.S# and SC.C#=Course.C# ;?
36、查詢?nèi)魏我婚T課程成績在70分以上的姓名、課程名稱和分?jǐn)?shù)；?
? ? SELECT ?distinct student.S#,student.Sname,SC.C#,SC.score?
? ? FROM student,Sc?
? ? WHERE SC.score>=70 AND SC.S#=student.S#;?
37、查詢不及格的課程，并按課程號(hào)從大到小排列?
? ? select c# from sc where scor e <60 order by C# ;?
38、查詢課程編號(hào)為003且課程成績在80分以上的學(xué)生的學(xué)號(hào)和姓名；?
? ? select SC.S#,Student.Sname from SC,Student where SC.S#=Student.S# and Score>80 and C#='003';?
39、求選了課程的學(xué)生人數(shù)?
? ? 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(gè)課程及相應(yīng)的選修人數(shù)?
? ? select count(*) from sc group by C#;?
42、查詢不同課程成績相同的學(xué)生的學(xué)號(hào)、課程號(hào)、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(jì)每門課程的學(xué)生選修人數(shù)（超過10人的課程才統(tǒng)計(jì)）。要求輸出課程號(hào)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(hào)升序排列 ?
? ? select ?C# as 課程號(hào),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(hào)?
? ? 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(hào)和課程名?
? ? select ?C#,Cname ?
? ? from ?Course ?
? ? where ?C# ?in ?(select ?c# ?from ?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(hào)及其平均成績?
? ? 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、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(hào)?
? ? select S# from SC where C#='004'and score <60 order by score desc;?
50、刪除“002”同學(xué)的“001”課程的成績?
delete from Sc where S#='002'and C#='001';?
建表語句
-- Create table create table DB_IMP_SC (S# NUMBER not null,C# NUMBER,SCORE VARCHAR2(10) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_SCis ' 成績表 '; -- Add comments to the columns comment on column DB_IMP_SC.S#is '學(xué)號(hào)'; comment on column DB_IMP_SC.C#is '課程編號(hào)'; comment on column DB_IMP_SC.SCOREis '成績';
-- Create table create table DB_IMP_STUDENT (S# NUMBER not null,SNAME VARCHAR2(12),SAGE VARCHAR2(3),SSEX VARCHAR2(2) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_STUDENTis ' 學(xué)生表'; -- Add comments to the columns comment on column DB_IMP_STUDENT.S#is '學(xué)號(hào)'; comment on column DB_IMP_STUDENT.SNAMEis '學(xué)生姓名'; comment on column DB_IMP_STUDENT.SAGEis '學(xué)生年齡'; comment on column DB_IMP_STUDENT.SSEXis '學(xué)生性別 ';
-- Create table create table DB_IMP_TEACHER (T# NUMBER not null,TNAME VARCHAR2(12) ) tablespace SYSTEMpctfree 10pctused 40initrans 1maxtrans 255storage(initial 64Kminextents 1maxextents unlimited); -- Add comments to the table comment on table DB_IMP_TEACHERis '教師表 '; -- Add comments to the columns comment on column DB_IMP_TEACHER.T#is '教師編號(hào)'; comment on column DB_IMP_TEACHER.TNAMEis '教師名字';
經(jīng)典！
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