分组字符累加。急。。。。

[deepsea0918]

如下：
name cust
wang aaa
wang bbb
wang ccc
chen ddd
chen aaa
liu eee
liu fff

如何用一条语句得到如下结果
wang aaa bbb ccc
chen aaa ddd
liu eee ffff

求教，多谢。。。

[hao1hao2hao3]

找找列传行的帖子，CSDN上很多的。

[zc_0101]

--合并分拆表
/******************************************************************************************************************************************************
合并分拆表数据

整理人：中国风(Roy)

日期:2008.06.06
******************************************************************************************************************************************************/

--> --> (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('<Tab>
                {for $i in /Tab[position()<last()]/@COl2 return concat(string($i),",")}
                {concat("",string(/Tab[last()]/@COl2))}
                </Tab>')
                )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:
/*
Col1        COl2
----------- ------------
1           a,b,c
2           d,e
3           f

(3 行受影响)
*/


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,'<root><v>'+replace(COl2,',','</v><v>')+'</v></root>') 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:
/*
Col1        COl2
----------- -----
1           a
1           b
1           c
2           d
2           e
3           f
*/

[andy_liucj]

你没说清楚
wang aaa bbb ccc
chen aaa ddd
liu eee ffff
这是4列还是2列

[pt1314917]

--> 测试数据: [tb]
if object_id('[tb]') is not null drop table [tb]
create table [tb] (name varchar(4),cust varchar(3))
insert into [tb]
select 'wang','aaa' union all
select 'wang','bbb' union all
select 'wang','ccc' union all
select 'chen','ddd' union all
select 'chen','aaa' union all
select 'liu','eee' union all
select 'liu','fff'
go

declare @sql varchar(8000)
set @sql='select name'
select @sql=@sql+',[col'+LTRIM(px)+']=max(case px when '+LTRIM(px)+' then cust else null end)'
from (select distinct px=(select COUNT(1) from tb where name=a.name and cust<=a.cust) from tb a)a
set @sql=@sql+' from (select *,px=(select COUNT(1) from tb where name=a.name and cust<=a.cust) from tb a)a group by name'
exec(@sql)