SQL2005下利用XML进行项目的合并与拆分

SQL2005下利用XML进行项目的合并与拆分<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

作者：HappyFlyStone

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　　通常情况下我们对相同数值项目进行分组求和，那是相当的简单啦，只要select.. group by加聚合函数就行了，可是对于串一类的项目进行合并时就不这么简单了，同样分解一个按指定分隔符分隔的串或分析指定位置的串，在下我们通常是创建一个函数，然后分组或提取就行了，现我们主要讨论在下利用xml来完成这个工作。

　　1、先来一个简单点，如下的例子对aaa相同的项目合并。

------------------------------------------------------------------------

-- Author: HappyFlyStone

-- Date : 2009-01-04 20:57:59

-- Ver: Microsoft SQL Server 2005 - 9.00.2047.00 (Intel X86)

-- Apr 14 2006 01:12:25

-- Copyright (c) 1988-2005 Microsoft Corporation

-- Standard Edition on Windows NT5.0(Build 2195: Service Pack 4)

--

------------------------------------------------------------------------

-- Test Data: tb

IF OBJECT_ID('tb') IS NOT NULL

DROP TABLE tb

Go

CREATE TABLE tb(aaa INT,bbb INT)

Go

INSERT INTO tb

SELECT 1,2 UNION ALL

SELECT 1,3 UNION ALL

SELECT 1,4 UNION ALL

SELECT 2,2 UNION ALL

SELECT 2,5

GO

--查询1

select

aaa,

[values]=stuff(replace(replace((select [bbb]

from tb

where aaa=t.aaa for xml AUTO),

'"/><tb bbb="',','),

'"/>',''),1,9,'')

from tb t

group by aaa

--查询2

SELECT *

FROM(

SELECT DISTINCT

aaa

FROM tb

)A

OUTER APPLY(

SELECT

[bbb]= STUFF(REPLACE(REPLACE(

(

SELECT [bbb] FROM tb N

WHERE aaa = A.aaa

FOR XML AUTO

), '<N bbb="', ','), '"/>', ''), 1, 1, '')

)N

--查询3

select

aaa,

[values]=stuff((select ','+ltrim([bbb])

from tb t

where aaa=tb.aaa for xml path('')), 1, 1, '')

from tb

group by aaa

drop table tb

--查询结果

/*

aaa values

----------- ---------

1 2,3,4

2 2,5

(2 行受影响)

*/

2、来个两个表关联操作并实现行列转换的

------------------------------------------------------------------------

-- Author: HappyFlyStone

-- Date : 2009-01-04 20:57:59

-- Ver: Microsoft SQL Server 2005 - 9.00.2047.00 (Intel X86)

-- Apr 14 2006 01:12:25

-- Copyright (c) 1988-2005 Microsoft Corporation

-- Standard Edition on Windows NT5.0(Build 2195: Service Pack 4)

--

------------------------------------------------------------------------

-- Test Data: ta

IF OBJECT_ID('ta') IS NOT NULL

DROP TABLE ta

Go

CREATE TABLE ta(pid INT,tid INT,name NVARCHAR(6))

Go

INSERT INTO ta

SELECT 1,1,'hy3500' UNION ALL

SELECT 1,2,'aabbcc' UNION ALL

SELECT 2,3,'1111' UNION ALL

SELECT 2,4,'2222'

GO

-- Test Data: tb

IF OBJECT_ID('tb') IS NOT NULL

DROP TABLE tb

Go

CREATE TABLE tb(NAME NVARCHAR(2),id INT)

Go

INSERT INTO tb

SELECT '型号',1 UNION ALL

SELECT '参数',2

GO

--Start

SELECT t.[name],A,B

FROM(

SELECT

B.[NAME],

CAST((SELECT [name] FROM TA WHERE PID = A.PID FOR XML PATH('')) AS XML) AS X

FROM TA A