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#,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# havingavg(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 Studentleft
Outer
join SCon 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 Tnamelike
'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 (selectdistinct( SC.S#)from
SC,Course,Teacherwhere 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.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 ,Teacherwhere
SC.C#=Course.C#and Teacher.T#=Course.T#and
Teacher.Tname='葉平'group
by S#
havingcount(SC.C#)=(selectcount(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”課程低的所有同學的學號、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,SCwhere S.S#=SC.S#and score>60);
10、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.Snamehaving
count(C#)
<(selectcount(C#)
from Course);
11、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#,Snamefrom Student,SCwhere Student.S#=SC.S#and
C# in
select C#from SC
where S#='1001';
12、查詢至少學過學號爲“001”同學所有一門課的其他同學學號和姓名;
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爲此課程的平均成績;
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='葉平');
14、查詢和“1002”號的同學學習的課程完全相同的其他同學學號和姓名;
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、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';
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“003”課程的同學學號、2、
號課的平均成績;
Insert SCselect S#,'002',(Selectavg(score)
from SCwhere C#='002')from
Studentwhere S#
not
in (Select S#from SC
where C#='002');
17、按平均成績從高到低顯示所有學生的“數據庫”、“企業管理”、“英語”三門的課程成績,按如下形式顯示: 學生ID,,數據庫,企業管理,英語,有效課程數,有效平均分
SELECT S#as 學生ID
,(SELECT scoreFROM SC
WHERE SC.S#=t.S#AND C#='004')AS
數據庫
,(SELECT scoreFROM SC
WHERE SC.S#=t.S#AND C#='001')AS
企業管理
,(SELECT scoreFROM SC
WHERE SC.S#=t.S#AND C#='006')AS
英語
,COUNT(*)AS 有效課程數,
AVG(t.score)
AS 平均成績
FROM SCAS 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.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、按各科平均成績從低到高和及格率的百分數從高到低順序
SELECT t.C#AS 課程號,max(course.Cname)AS
課程名,isnull(AVG(score),0)AS
平均成績
,100*
SUM(CASEWHEN
isnull(score,0)>=60THEN
1ELSE
0END)/COUNT(*)AS
及格百分數
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、查詢如下課程平均成績和及格率的百分數(用"1行"顯示): 企業管理(001),馬克思(002),OO&UML
(003),數據庫(004)
SELECT
SUM(CASEWHEN C#
='001'THEN score
ELSE
0END)/SUM(CASE
C# WHEN
'001'THEN
1ELSE
0END)
AS 企業管理平均分
,100*
SUM(CASEWHEN C#
= '001'AND
score >=
60THEN
1ELSE
0END)/SUM(CASEWHEN
C# =
'001'THEN
1ELSE
0END)
AS 企業管理及格百分數
,SUM(CASEWHEN C#
= '002'THEN
score ELSE
0END)/SUM(CASE
C# WHEN
'002'THEN
1ELSE
0END)
AS 馬克思平均分
,100*
SUM(CASEWHEN C#
= '002'AND
score >=
60THEN
1ELSE
0END)/SUM(CASEWHEN
C# =
'002'THEN
1ELSE
0END)
AS 馬克思及格百分數
,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及格百分數
,SUM(CASEWHEN C#
= '004'THEN
score ELSE
0END)/SUM(CASE
C# WHEN
'004'THEN
1ELSE
0END)
AS 數據庫平均分
,100*
SUM(CASEWHEN C#
= '004'AND
score >=
60THEN
1ELSE
0END)/SUM(CASEWHEN
C# =
'004'THEN
1ELSE
0END)
AS 數據庫及格百分數
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 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、查詢如下課程成績第3 名到第6
名的學生成績單:企業管理(001),馬克思(002),UML (003),數據庫(004)
[學生ID],[學生姓名],企業管理,馬克思,UML,數據庫,平均成績
SELECT DISTINCT
top
3
SC.S# As 學生學號,
Student.Sname AS 學生姓名 ,
T1.score AS 企業管理,
T2.score AS 馬克思,
T3.score AS UML,
T4.score AS 數據庫,
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'
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、統計列印各科成績,各分數段人數:課程ID,課程名稱,[100-85],[85-70],[70-60],[
<60]
SELECT SC.C#as 課程ID, Cnameas
課程名稱
,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、查詢學生平均成績及其名次
SELECT1+(SELECTCOUNT(
distinct 平均成績)
FROM (SELECT S#,AVG(score)AS
平均成績
FROM SC
GROUPBY S#
) AS T1
WHERE 平均成績> T2.平均成績)
as 名次,
S# as 學生學號,平均成績
FROM (SELECT S#,AVG(score)
平均成績
FROM SC
GROUPBY S#
) AS T2
ORDER
BY 平均成績 desc;
25、查詢各科成績前三名的記錄:(不考慮成績並列情況)
SELECT t1.S#as 學生ID,t1.C#as 課程ID,Scoreas
分數
FROM SC t1
WHERE scoreIN (SELECTTOP
3 score
FROM SC
WHERE t1.C#= C#
ORDERBY score
DESC
)
ORDERBY t1.C#;
26、查詢每門課程被選修的學生數
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生的學號和姓名
select SC.S#,Student.Sname,count(C#)AS
選課數
from SC ,Student
where SC.S#=Student.S#group
by SC.S# ,Student.Snamehaving
count(C#)=1;
28、查詢男生、女生人數
Select
count(Ssex)
as 男生人數 from Studentgroup
by Ssex
having Ssex='男';
Select
count(Ssex)
as 女生人數 from Studentgroup
by Ssex
having Ssex='女';
29、查詢姓“張”的學生名單
SELECT SnameFROM StudentWHERE Snamelike
'張%';
30、查詢同名同性學生名單,並統計同名人數
select Sname,count(*)from
Studentgroup
by Sname
having count(*)>1;;
31、1981年出生的學生名單(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、查詢平均成績大於85的所有學生的學號、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、查詢課程名稱爲“數據庫”,且分數低於60的學生姓名和分數
Select Sname,isnull(score,0)
from Student,SC,Course
where SC.S#=Student.S#and SC.C#=Course.C#and
Course.Cname='數據庫'and score
<60;
35、查詢所有學生的選課情況;
SELECT SC.S#,SC.C#,Sname,Cname
FROM SC,Student,Course
where SC.S#=Student.S#and SC.C#=Course.C#
;
36、查詢任何一門課程成績在70分以上的姓名、課程名稱和分數;
SELECT distinct student.S#,student.Sname,SC.C#,SC.score
FROM student,Sc
WHERE SC.score>=70AND
SC.S#=student.S#;
37、查詢不及格的課程,並按課程號從大到小排列
select c#from sc
where scor e
<60order
by C# ;
38、查詢課程編號爲003且課程成績在80分以上的學生的學號和姓名;
select SC.S#,Student.Snamefrom SC,Studentwhere
SC.S#=Student.S#and Score>80and
C#='003';
39、求選了課程的學生人數
select
count(*)from sc;
40、查詢選修“葉平”老師所授課程的學生中,成績最高的學生姓名及其成績
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=(selectmax(score)from
SCwhere C#=C.C# );
41、查詢各個課程及相應的選修人數
select
count(*)from sc
group
by C#;
42、查詢不同課程成績相同的學生的學號、課程號、學生成績
select
distinct A.S#,B.scorefrom SC A ,SC Bwhere A.Score=B.Scoreand
A.C# <>B.C# ;
43、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,Scoreas
分數
FROM SC t1
WHERE scoreIN (SELECTTOP
2 score
FROM SC
WHERE t1.C#= C#
ORDERBY score
DESC
)
ORDERBY t1.C#;
44、統計每門課程的學生選修人數(超過10人的課程才統計)。要求輸出課程號和選修人數,查詢結果按人數降序排列,查詢結果按人數降序排列,若人數相同,按課程號升序排列
select C#as 課程號,count(*)as
人數
from sc
group
by C#
order
by count(*)desc,c#
45、檢索至少選修兩門課程的學生學號
select S#
from sc
group
by s#
having count(*) >
= 2
46、查詢全部學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# from
sc group
by c#)
47、查詢沒學過“葉平”老師講授的任一門課程的學生姓名
select Snamefrom Studentwhere S#
not
in (select S#from Course,Teacher,SCwhere
Course.T#=Teacher.T#and SC.C#=course.C#and
Tname='葉平');
48、查詢兩門以上不及格課程的同學的學號及其平均成績
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、檢索“004”課程分數小於60,按分數降序排列的同學學號
select S#from SC
where C#='004'and
score <60order
by score
desc;
50、刪除“002”同學的“001”課程的成績
delete
from Sc where S#='001'and
C#='001';