比方有表Table,字段有:ID(int),TID(int,外键),AID(int,另一个数据表的外键)。
Table:
ID TID AID
1 1 1
2 2 1
3 1 2
4 2 2
5 5 2
6 3 3求一SQL语句实现如下效果:
Table:
AID TID的集合
1 1,2
2 1,2,5
3 3 也就是根据AID进行分类,同一个AID对应的TID组合到一个字段里面去。期待各位解答,谢谢了!
Table:
ID TID AID
1 1 1
2 2 1
3 1 2
4 2 2
5 5 2
6 3 3求一SQL语句实现如下效果:
Table:
AID TID的集合
1 1,2
2 1,2,5
3 3 也就是根据AID进行分类,同一个AID对应的TID组合到一个字段里面去。期待各位解答,谢谢了!
/******************************************************************************************************************************************************
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 TabgoSQL2005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>')
)bSQL05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'
GoSQL2000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
-- Author :fredrickhu(我是小F,向高手学习)
-- Date :2009-11-05 11:59:01
-- Version:
-- Microsoft SQL Server 2005 - 9.00.4035.00 (Intel X86)
-- Nov 24 2008 13:01:59
-- Copyright (c) 1988-2005 Microsoft Corporation
-- Developer Edition on Windows NT 5.2 (Build 3790: Service Pack 1)
--
----------------------------------------------------------------
--> 测试数据:[tb]
if object_id('[tb]') is not null drop table [tb]
go
create table [tb]([ID] int,[TID] int,[AID] int)
insert [tb]
select 1,1,1 union all
select 2,2,1 union all
select 3,1,2 union all
select 4,2,2 union all
select 5,5,2 union all
select 6,3,3
--------------开始查询--------------------------
select aid, [tid]=stuff((select ','+ltrim([tid]) from tb t where aid=tb.aid for xml path('')), 1, 1, '')
from tb
group by aid
----------------结果----------------------------
/* aid tid
----------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 1,2
2 1,2,5
3 3(3 行受影响)*/
return varchar(30)
as
begin
declare @temp varchar(20)
set @temp=''
select @temp=@temp+cast(tid as varchar)
from tb
return @temp
endselect aid,test(aid)
from tb
group by aid
-- Author :fredrickhu(我是小F,向高手学习)
-- Date :2009-11-05 11:59:01
-- Version:
-- Microsoft SQL Server 2005 - 9.00.4035.00 (Intel X86)
-- Nov 24 2008 13:01:59
-- Copyright (c) 1988-2005 Microsoft Corporation
-- Developer Edition on Windows NT 5.2 (Build 3790: Service Pack 1)
--
----------------------------------------------------------------
--> 测试数据:[tb]
if object_id('[tb]') is not null drop table [tb]
go
create table [tb]([ID] int,[TID] int,[AID] int)
insert [tb]
select 1,1,1 union all
select 2,2,1 union all
select 3,1,2 union all
select 4,2,2 union all
select 5,5,2 union all
select 6,3,3
--------------开始查询--------------------------
select aid, [tid]=stuff((select ','+ltrim([tid]) from tb t where aid=tb.aid for xml path('')), 1, 1, '')
from tb
group by aid CREATE FUNCTION dbo.f_strUnite(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @str varchar(8000)
SET @str = ''
SELECT @str = @str + ',' + ltrim(tid) FROM tb WHERE aid=@id
RETURN STUFF(@str, 1, 1, '')
END
GO
-- 调用函数
SELECt aid, tid = dbo.f_strUnite(aid) FROM tb GROUP BY tid
drop table tb
drop function dbo.f_strUnite
go
----------------结果----------------------------
/* aid tid
----------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 1,2
2 1,2,5
3 3(3 行受影响)*/