行轉列
一張表
查詢結果為
--行轉列
select years,(select amount from Tb_Amount as A where month=1 and A.years=Tb_Amount.years)as m1,(select amount from Tb_Amount as A where month=2 and A.years=Tb_Amount.years)as m2,(select amount from Tb_Amount as A where month=3 and A.years=Tb_Amount.years)as m3from Tb_Amount group by years
或者為
select years as 年份,sum(case when month='1' then amount end) as 一月, sum(case when month='2' then amount end) as 二月,sum(case when month='3' then amount end) as 三月from dbo.Tb_Amount group by years order by years desc
2.人員信息表包括姓名 時代 金額
顯示行轉列
姓名 時代 金額
姓名 年輕 中年 老年
張麗 1000000.00 4000000.00 500000000.00
孫子 2000000.00 12233335.00 4552220010.00
select uname as 姓名,SUM(case when era='年輕' then amount end) as 年輕,SUM(case when era='中年' then amount end) as 中年,SUM(case when era='老年' then amount end) as 老年from Tb_People group by uname order by uname desc
3.學生表 [Tb_Student]
顯示效果
靜態SQL,指subject只有語文、數學、英語這三門課程。
select sname as 姓名,max(case Subject when '語文' then grade else 0 end) as 語文,max(case Subject when '數學' then grade else 0 end) as 數學,max(case Subject when '英語' then grade else 0 end) as 英語from dbo.Tb_Student group by sname order by sname desc
--動態SQL,指subject不止語文、數學、英語這三門課程。
declare @sql varchar(8000)set @sql = 'select sname as ' + '姓名'select @sql = @sql + ' , max(case Subject when ''' + Subject + ''' then grade else 0 end) [' + Subject + ']'from (select distinct Subject from Tb_Student) as aset @sql = @sql + ' from Tb_Student group by sname order by sname desc'exec(@sql)
oracle中Decode()函數使用 然后將這些累計求和(sum部分）
select t.sname AS 姓名,sum(decode(t.subject,'語文',grade,null))語文 ,sum(decode(t.subject,'數學',grade,null)) 數學,sum(decode(t.subject,'英語',grade,null)) 英語from Tb_Student t group by sname order by sname desc
列轉行
生成
sql代碼
生成靜態:
select *from (select sname,[Course ] ='數學',[Score]=[數學] from Tb_students union allselect sname,[Course]='英語',[Score]=[英語] from Tb_students union allselect sname,[Course]='語文',[Score]=[語文] from Tb_students)torder by sname,case [Course] when '語文' then 1 when '數學' then 2 when '英語' then 3 endgo --列轉行的靜態方案：UNPIVOT,sql2005及以后版本 SELECT sname,Subject, grade from dbo.Tb_students unpivot(grade for Subject in([語文],[數學],[英語]))as up GO --列轉行的動態方案：UNPIVOT,sql2005及以后版本 --因為行是動態所以這里就從INFORMATION_SCHEMA.COLUMNS視圖中獲取列來構造行，同樣也使用了XML處理。 declare @s nvarchar(4000)select @s=isnull(@s+',','')+quotename(Name)from syscolumns where ID=object_id('Tb_students') and Name not in('sname')order by Colidexec('select sname,[Subject],[grade] from Tb_students unpivot ([grade] for [Subject] in('+@s+'))b')goselect sname,[Subject],[grade]from Tb_studentsunpivot ([grade] for [Subject] in([數學],[英語],[語文]))b 
