【sqlserver】字段拆分

--sqlserver字段拆分 --xml解法 ------------- select id,t into #t from ( select 1 id,'aa,bb,cc' t union all select 2 id, 'aa,cc,dd' t ) t select * from #t /* 1 aa,bb,cc 2 aa,cc,dd */ select a.id,b.t from (select id,t=convert(xml,'<root><col val="'+replace(t,',','" /><col val="')+'"></col></root>') from #t) a outer apply (select t=C.v.value('@val','nvarchar(255)') from a.t.nodes('/root/col')C(v))b -----------未测试其他思路（转自：http://blog.sina.com.cn/s/blog_b3eabfd30102wldv.html） --合并分拆表 --> --> (Roy)生成測試數據 if not object_id('Tab') is null drop table Tab Go Create table Tab([Col1] int,[Col2] nvarchar(1)) Insert Tab select 1,N'a' union all select 1,N'b' union all select 1,N'c' union all select 2,N'd' union all select 2,N'e' union all select 3,N'f' Go 合并表: SQL2000用函数: go if object_id('F_Str') is not null drop function F_Str go create function F_Str(@Col1 int) returns nvarchar(100) as begin declare @S nvarchar(100) select @S=isnull(@S+',','')+Col2 from Tab where Col1=@Col1 return @S end go Select distinct Col1,Col2=dbo.F_Str(Col1) from Tab go SQL2005用XML: 方法1: select a.Col1,Col2=stuff(b.Col2.value('/R[1]','nvarchar(max)'),1,1,'') from (select distinct COl1 from Tab) a Cross apply (select COl2=(select N','+Col2 from Tab where Col1=a.COl1 For XML PATH(''), ROOT('R'), TYPE))b 方法2: select a.Col1,COl2=replace(b.Col2.value('/Tab[1]','nvarchar(max)'),char(44)+char(32),char(44)) from (select distinct COl1 from Tab) a cross apply (select Col2=(select COl2 from Tab where COl1=a.COl1 FOR XML AUTO, TYPE) .query(' {for $i in /Tab[position() {concat("",string(/Tab[last()]/@COl2))} ') )b SQL05用CTE: ;with roy as(select Col1,Col2,row=row_number()over(partition by COl1 order by COl1) from Tab) ,Roy2 as (select COl1,cast(COl2 as nvarchar(100))COl2,row from Roy where row=1 union all select a.Col1,cast(b.COl2+','+a.COl2 as nvarchar(100)),a.row from Roy a join Roy2 b on a.COl1=b.COl1 and a.row=b.row+1) select Col1,Col2 from Roy2 a where row=(select max(row) from roy where Col1=a.COl1) order by Col1 option (MAXRECURSION 0) 生成结果: 拆分表: --> --> (Roy)生成測試數據 if not object_id('Tab') is null drop table Tab Go Create table Tab([Col1] int,[COl2] nvarchar(5)) Insert Tab select 1,N'a,b,c' union all select 2,N'd,e' union all select 3,N'f' Go SQL2000用辅助表: if object_id('Tempdb..#Num') is not null drop table #Num go select top 100 ID=Identity(int,1,1) into #Num from syscolumns a,syscolumns b Select a.Col1,COl2=substring(a.Col2,b.ID,charindex(',',a.Col2+',',b.ID)-b.ID) from Tab a,#Num b where charindex(',',','+a.Col2,b.ID)=b.ID --也可用 substring(','+a.COl2,b.ID,1)=',' SQL2005用Xml: select a.COl1,b.Col2 from (select Col1,COl2=convert(xml,''+replace(COl2,',','')+'') from Tab)a outer apply (select Col2=C.v.value('.','nvarchar(100)') from a.COl2.nodes('/root/v')C(v))b SQL05用CTE: ;with roy as (select Col1,COl2=cast(left(Col2,charindex(',',Col2+',')-1) as nvarchar(100)),Split=cast(stuff(COl2+',',1,charindex(',',Col2+','),'') as nvarchar(100)) from Tab union all select Col1,COl2=cast(left(Split,charindex(',',Split)-1) as nvarchar(100)),Split= cast(stuff(Split,1,charindex(',',Split),'') as nvarchar(100)) from Roy where split>'' ) select COl1,COl2 from roy order by COl1 option (MAXRECURSION 0) 生成结果: