學生成績表(stuscore)：
| 姓名：name | 課程：subject | 分數：score | 學號：stuid |
| 張三 | 數學 | 89 | 1 |
| 張三 | 語文 | 80 | 1 |
| 張三 | 英語 | 70 | 1 |
| 李四 | 數學 | 90 | 2 |
| 李四 | 語文 | 70 | 2 |
| 李四 | 英語 | 80 | 2 |
創建表
SET ANSI_NULLS ONGOSET QUOTED_IDENTIFIER ONGOSET ANSI_PADDING ONGOCREATE TABLE [dbo].[stuscore]( [name] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL, [subject] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL, [score] [int] NULL, [stuid] [int] NULL) ON [PRIMARY] GOSET ANSI_PADDING OFF
問題：
1.計算每個人的總成績並排名(要求顯示字段：姓名，總成績)
2.計算每個人的總成績並排名(要求顯示字段: 學號，姓名，總成績)
3.計算每個人單科的最高成績(要求顯示字段: 學號，姓名，課程，最高成績)
4.計算每個人的平均成績（要求顯示字段: 學號，姓名，平均成績）
5.列出各門課程成績最好的學生(要求顯示字段: 學號，姓名,科目，成績)
6.列出各門課程成績最好的兩位學生(要求顯示字段: 學號，姓名,科目，成績)
7.統計如下：
| 學號 | 姓名 | 語文 | 數學 | 英語 | 總分 | 平均分 |
8．列出各門課程的平均成績（要求顯示字段：課程，平均成績）
9．列出數學成績的排名（要求顯示字段：學號，姓名，成績，排名）
10．列出數學成績在2-3名的學生（要求顯示字段：學號，姓名,科目，成績）
11．求出李四的數學成績的排名
12．統計如下：
| 課程 | 不及格（0-59）個 | 良（60-80）個 | 優（81-100）個 |
13．統計如下：數學:張三(50分),李四(90分),王五(90分),趙六(76分)
答案：
1.計算每個人的總成績並排名
select name,sum(score) as allscore from stuscore group by name order by allscore
2.計算每個人的總成績並排名
select distinct t1.name,t1.stuid,t2.allscore from stuscore t1,( select stuid,sum(score) as allscore from stuscore group by stuid)t2where t1.stuid=t2.stuidorder by t2.allscore desc
3. 計算每個人單科的最高成績
select t1.stuid,t1.name,t1.subject,t1.score from stuscore t1,(select stuid,max(score) as maxscore from stuscore group by stuid) t2where t1.stuid=t2.stuid and t1.score=t2.maxscore
4.計算每個人的平均成績
select distinct t1.stuid,t1.name,t2.avgscore from stuscore t1,(select stuid,avg(score) as avgscore from stuscore group by stuid) t2where t1.stuid=t2.stuid
5.列出各門課程成績最好的學生
select t1.stuid,t1.name,t1.subject,t2.maxscore from stuscore t1,(select subject,max(score) as maxscore from stuscore group by subject) t2where t1.subject=t2.subject and t1.score=t2.maxscore
6.列出各門課程成績最好的兩位學生
select distinct t1.* from stuscore t1 where t1.id in (select top 2 stuscore.id from stuscore where subject = t1.subject order by score desc) order by t1.subject
7.學號 姓名 語文 數學 英語 總分 平均分
select stuid as 學號,name as 姓名,sum(case when subject='語文' then score else 0 end) as 語文,sum(case when subject='數學' then score else 0 end) as 數學,sum(case when subject='英語' then score else 0 end) as 英語,sum(score) as 總分,(sum(score)/count(*)) as 平均分from stuscoregroup by stuid,name order by 總分desc
8.列出各門課程的平均成績
select subject,avg(score) as avgscore from stuscoregroup by subject
9.列出數學成績的排名
declare @tmp table(pm int,name varchar(50),score int,stuid int)insert into @tmp select null,name,score,stuid from stuscore where subject='數學' order by score descdeclare @id intset @id=0;update @tmp set @id=@id+1,pm=@idselect * from @tmp
select DENSE_RANK () OVER(order by score desc) as row,name,subject,score,stuid from stuscore where subject='數學'order by score desc
10. 列出數學成績在2-3名的學生
select t3.* from(select top 2 t2.* from (select top 3 name,subject,score,stuid from stuscore where subject='數學'order by score desc) t2 order by t2.score) t3 order by t3.score desc
11. 求出李四的數學成績的排名
declare @tmp table(pm int,name varchar(50),score int,stuid int)insert into @tmp select null,name,score,stuid from stuscore where subject='數學' order by score descdeclare @id intset @id=0;update @tmp set @id=@id+1,pm=@idselect * from @tmp where name='李四'
12. 課程 不及格（-59） 良（-80） 優（-100）
select subject, (select count(*) from stuscore where score<60 and subject=t1.subject) as 不及格,(select count(*) from stuscore where score between 60 and 80 and subject=t1.subject) as 良,(select count(*) from stuscore where score >80 and subject=t1.subject) as 優from stuscore t1 group by subject
13. 數學:張三(50分),李四(90分),王五(90分),趙六(76分)
declare @s varchar(1000)set @s=''select @s =@s+','+name+'('+convert(varchar(10),score)+'分)' from stuscore where subject='數學' set @s=stuff(@s,1,1,'')print '數學:'+@s