整理的方法如下：
Title: 在SQL中分类合并数据行
Author: dobear Mail(MSN): dobear_0922@hotmail.com
Environment: Vista + SQL2005
Date: 20080422
1. 创建表，添加测试数据
CREATE TABLE tb(id int, [value] varchar(10))
INSERT tb SELECT 1, 'aa'
UNION ALL SELECT 1, 'bb'
UNION ALL SELECT 2, 'aaa'
UNION ALL SELECT 2, 'bbb'
UNION ALL SELECT 2, 'ccc'
SELECT FROM tb
///
id value
1 aa
1 bb
2 aaa
2 bbb
2 ccc
(5 row(s) affected)
/
2 在SQL2000只能用自定义函数实现
2.1 创建合并函数fn_strSum，根据id合并value值
GO
CREATE FUNCTION dbo.fn_strSum(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @values varchar(8000)
SET @values = ''
SELECT @values = @values + ',' + value FROM tb WHERE id=@id
RETURN STUFF(@values, 1, 1, '')
END
GO
调用函数
SELECT id, VALUE = dbo.fn_strSum(id) FROM tb GROUP BY id
DROP FUNCTION dbo.fn_strSum
2.2 创建合并函数fn_strSum2，根据id合并value值
GO
CREATE FUNCTION dbo.fn_strSum2(@id int)
RETURNS varchar(8000)
AS
BEGIN
DECLARE @values varchar(8000)
SELECT @values = isnull(@values + ',', '') + value FROM tb WHERE id=@id
RETURN @values
END
GO
调用函数
SELECT id, VALUE = dbo.fn_strSum2(id) FROM tb GROUP BY id
DROP FUNCTION dbo.fn_strSum2
3 在SQL2005中的新解法
3.1 使用OUTER APPLY
SELECT
FROM (SELECT DISTINCT id FROM tb) A OUTER APPLY(
SELECT [values]= STUFF(REPLACE(REPLACE(
(
SELECT value FROM tb N
WHERE id = A.id
FOR XML AUTO
), '<N value="', ','), '"/>', ''), 1, 1, '')
)N
3.2 使用XML
SELECT id, [values]=STUFF((SELECT ','+[value] FROM tb t WHERE id=tb.id FOR XML PATH('')), 1, 1, '')
FROM tb
GROUP BY id
4 删除测试表tb
drop table tb
///
id values
1 aa,bb
2 aaa,bbb,ccc
(2 row(s) affected)
/
roy_88 兄弟整理的方法：
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
责任编辑：小草
