經典的SQL語句面試題

Student(S#,Sname,Sage,Ssex) 學生表
Course(C#,Cname,T#) 課程表
SC(S#,C#,score) 成績表
Teacher(T#,Tname) 教師表 

問題:
1、查詢“001”課程比“002”課程成績高的所有學生的學號;
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、查詢平均成績大於60分的同學的學號和平均成績;
select S#,avg(score)
from sc
group by S# having avg(score) >60; 

3、查詢所有同學的學號、姓名、選課數、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;
select count(distinct(Tname))
from Teacher
where Tname like ‘李%’; 

5、查詢沒學過“葉平”老師課的同學的學號、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、查詢學過“001”並且也學過編號“002”課程的同學的學號、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、查詢學過“葉平”老師所教的所有課的同學的學號、姓名;
select S#,Sname
from Student
where S# in
(select S#
from SC ,Course ,Teacher
where SC.C#=Course.C# and Teacher.T#=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、查詢所有課程成績小於60分的同學的學號、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); 

9、查詢沒有學全所有課的同學的學號、姓名;
select Student.S#,Student.Sname
from Student,SC
where Student.S#=SC.S#
group by Student.S#,Student.Sname having count(C#) <(select count(C#) from Course); 

10、查詢至少有一門課與學號爲“1001”的同學所學相同的同學的學號和姓名;
select S#,Sname
from Student,SC
where Student.S#=SC.S# and C# in (select C# from SC where S#='1001');

11、刪除學習“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'; 

12、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# 課程ID,L.score 最高分,R.score 最低分
FROM SC L ,SC R
WHERE L.C# = R.C#
and
L.score = (SELECT MAX(IL.score)
FROM SC IL,Student IM
WHERE IL.C# = L.C# and IM.S#=IL.S#
GROUP BY IL.C#)
and
R.Score = (SELECT MIN(IR.score)
FROM SC IR
WHERE IR.C# = R.C#
GROUP BY IR.C# ); 

13、查詢學生平均成績及其名次
SELECT 1+(SELECT COUNT( distinct 平均成績)
FROM (SELECT S#,AVG(score) 平均成績
FROM SC
GROUP BY S# ) T1
WHERE 平均成績 > T2.平均成績) 名次, S# 學生學號,平均成績
FROM (SELECT S#,AVG(score) 平均成績 FROM SC GROUP BY S# ) T2
ORDER BY 平均成績 desc;

14、查詢各科成績前三名的記錄:(不考慮成績並列情況)
SELECT t1.S# as 學生ID,t1.C# as 課程ID,Score as 分數
FROM SC t1
WHERE score IN (SELECT TOP 3 score
FROM SC
WHERE t1.C#= C#
ORDER BY score DESC)
ORDER BY t1.C#; 

15、查詢每門功成績最好的前兩名
SELECT t1.S# as 學生ID,t1.C# as 課程ID,Score as 分數
FROM SC t1
WHERE score IN (SELECT TOP 2 score
FROM SC
WHERE t1.C#= C#
ORDER BY score DESC )
ORDER BY t1.C#;

補充:
已經知道原表
year salary
——————
2000 1000
2001 2000
2002 3000
2003 4000

解:
select b.year,sum(a.salary)
from salary a,salary b
where a.year<=b.year
group by b.year
order by b.year;

在面試過程中多次碰到一道SQL查詢的題目,查詢A(ID,Name)表中第31至40條記錄,ID作爲主鍵可能是不是連續增長的列,完整的查詢語句如下:
方法一:
select top 10 *
from A
where ID >(select max(ID) from (select top 30 ID from A order by ID ) T) order by ID
方法二:
select top 10 *
from A
where ID not In (select top 30 ID from A order by ID)
order by ID
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