創建表 插入數據 查詢結果顯示,如下截圖: 問題: 1.計算每個人的總成績併排名(要求顯示欄位:姓名,總成績) select name,SUM(score) as allscore from dbo.stuscore group by name order by allscore; View Cod ...
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] GO SET ANSI_PADDING OFF
插入數據
insert into dbo.stuscore values ('張三','數學',89,1); insert into dbo.stuscore values ('張三','語文',80,1); insert into dbo.stuscore values ('張三','英語',70,1); insert into dbo.stuscore values ('李四','數學',90,2); insert into dbo.stuscore values ('李四','語文',70,2); insert into dbo.stuscore values ('李四','英語',80,2);
查詢結果顯示,如下截圖:
問題: 1.計算每個人的總成績併排名(要求顯示欄位:姓名,總成績)select name,SUM(score) as allscore from dbo.stuscore group by name order by allscore;View Code
2.計算每個人的總成績併排名(要求顯示欄位: 學號,姓名,總成績)
select stuid,name,SUM(score) as allscore from dbo.stuscore group by name,stuid order by allscore;View Code 3.計算每個人單科的最高成績(要求顯示欄位: 學號,姓名,課程,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) t2 where t1.stuid=t2.stuid and t1.score=t2.maxscore;View Code 4.計算每個人的平均成績(要求顯示欄位: 學號,姓名,平均成績)
select stuid,name,AVG(score) avgscore from dbo.stuscore group by stuid,name;View Code 5.列出各門課程成績最好的學生(要求顯示欄位: 學號,姓名,科目,成績)
select t1.stuid,t1.name,t1.subject,t1.score from stuscore t1,( select subject,MAX(score) as maxscore from stuscore group by subject)t2 where t1.subject = t2.subject and t1.score = t2.maxscore;View Code 6.列出各門課程成績最好的兩位學生(要求顯示欄位: 學號,姓名,科目,成績)
select t1.* from stuscore t1 where t1.stuid in ( select top 2 stuid from stuscore where subject = t1.subject order by score desc) order by t1.subject;View Code 7.統計如下:
學號 | 姓名 | 語文 | 數學 | 英語 | 總分 | 平均分 |
select stuid 學號,name 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)總分,avg(score)平均分 from stuscore group by stuid,name order by 總分;View Code 8.列出各門課程的平均成績(要求顯示欄位:課程,平均成績)
select subject,AVG(score)平均成績 from stuscore group by subject;View Code 9.列出數學成績的排名(要求顯示欄位:學號,姓名,成績,排名)
select stuid,name,score, (select count(*) from stuscore t1 where subject ='數學' and t1.score > t2.score)+1 as 名次 from stuscore t2 where subject='數學' order by score desc; --註釋:排序,比較大小,比較的次數+1 = 排名。View Code 10.列出數學成績在2-3名的學生(要求顯示欄位:學號,姓名,科目,成績)
select t3.* from ( select top 2 t2.* from ( select top 3 stuid,name,subject,score from stuscore where subject = '數學' order by score desc) t2 order by t2.score) t3 order by t3.score desc;View Code
select t3.* from ( select top 100 percent stuid,name,subject,score, (select count(*) from stuscore t1 where subject ='數學' and t1.score > t2.score)+1 as 名次 from stuscore t2 where subject='數學' order by t2.score desc) t3 where t3.名次 between 2 and 3 order by t3.score desc;View Code
select t3.* from ( select stuid,name,subject,score, (select count(*) from stuscore t1 where subject ='數學' and t1.score > t2.score)+1 as 名次 from stuscore t2 where subject='數學') t3 where t3.名次 between 2 and 3 order by t3.score desc;View Code
後面兩個方法的不同之處可以參見:http://blog.csdn.net/wrm_nancy/article/details/17170115
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 desc declare @id int set @id=0; update @tmp set @id=@id+1,pm=@id select * from @tmp where name='李四'View Code
select stuid,name,subject,score,(select count(*) from stuscore t1 where subject ='數學' and t1.score > t2.score)+1 as 名次 from stuscore t2 where subject='數學' and name = '李四' order by score desc;View Code 12.統計如下:
課程 | 不及格(0-59)個 | 良(60-80)個 | 優(81-100)個 |
select subject 科目,sum(case when score between 0 and 59 then 1 else 0 end) as 不及格, sum(case when score between 60 and 80 then 1 else 0 end) as 良, sum(case when score between 81 and 100 then 1 else 0 end) as 優秀 from stuscore group by subject;View Code 13.統計如下: 數學: 張三(50分),李四(90分),王五(90分),趙六(76分)
declare @s nvarchar(1000) set @s='' select @s =@s+','+name+'('+convert(nvarchar(10),score)+'分)' from stuscore where subject='數學' set @s=stuff(@s,1,1,' ')print '數學:'+@sView Code