實驗三:

select sno,sname

from student;//(1)查詢全體學生的學號和姓名

select *

from student;//(2)查詢全體學生的詳細記錄

select sname,sage,sdept

from student where sdept='MA';//(3)查詢軟件學院的學生姓名、年齡、系別

select distinct sno

from sc;//(4)查詢所有選修過課程的學生學號(不重復)

select distinct sno

from sc

where grade<60;//(5)查詢考試不及格的學生學號(不重復)

select ssex,sage,sdept

from student

where sdept not in('CS','MA');//(6)查詢不是軟件學院、計算機系的學生性別、年齡、系別

select sno,sname,sdept,sage

from student

where sage>=18 and sage<=20;//(7)查詢年齡18－20歲的學生學號、姓名、系別、年齡；

select *

from student

where sname like '劉%';//(8)查詢姓劉的學生情況

select *

from student

where sname like '劉%'or sname like '李%';//(9)查詢姓劉或姓李的學生情況

select *

from student

where sname like '劉_';//(10)查詢姓劉且名字為兩個字的學生情況

select sname

from student

where sage<31;//(11)查詢1983年以后出生的學生姓名。

create table studentgrade

(

sno char(8) PRimary key,

mathgrade tinyint,

englishgrade tinyint,

chinesegrade tinyint

)

go

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95001',85,95,74)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95002',86,91,70)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95003',80,92,71)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95004',81,91,75)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95005',87,97,78)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95006',81,97,70)

insert into studentgrade(sno,mathgrade,englishgrade,chinesegrade) values( '95007',85,95,70)

select sum(mathgrade+englishgrade+chinesegrade) as sumgrades

from studentgrade group by sno;(12)創建表 studentgrade(sno,mathgrade,englishigrade,chinesegrade)

計算學生各科總成績并賦予別名

select (year(getdate())-student.sage+1)

from student

where sdept='MA';//(13)利用內部函數 year()查找軟件學院學生的出生年份

select sname + '年齡為'+cast(sage as char(2))+'歲'

from student;

Select sname + ‘年齡為’+cast(sage as char(2))+’歲’

From student//(14)利用字符轉換函數實現字符聯接。

select*

from student order by sdept,sage desc;//(15)查詢全體學生情況，查詢結果按所在系升序排列，對同一系中的學生按年齡降序排列。

select count(*)

from student;//查詢總人數

select count(distinct sno)

from sc;//查詢選修了課程的學生人數

select count(*),avg(grade)as avggrade

from student ,sc

where student.sno=sc.sno and sc.cno='1';//(18)查詢選修了7號課程的學生總人數和平均成績

select max(grade) as maxgrade

from sc

where cno='2';//(19)查詢選修6號課程學生的最好成績

select sdept,count(*)

from student group by sdept;//(20)查詢每個系的系名及學生人數。

select cno,count(*),avg(grade) as avggrade

from sc group by cno;//(21)查找每門課的選修人數及平均成績

select *

from course

where cpno is null;//(22)查找沒有先修課的課程情況

總結

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