日期:2014-05-18 浏览次数:20718 次
合并列值 --******************************************************************************************* 表结构,数据如下: id value ----- ------ 1 aa 1 bb 2 aaa 2 bbb 2 ccc 需要得到结果: id values ------ ----------- 1 aa,bb 2 aaa,bbb,ccc 即:group by id, 求 value 的和(字符串相加) 1. 旧的解决方法(在sql server 2000中只能用函数解决。) --============================================================================= create table tb(id int, value varchar(10)) insert into tb values(1, 'aa') insert into tb values(1, 'bb') insert into tb values(2, 'aaa') insert into tb values(2, 'bbb') insert into tb values(2, 'ccc') go --1. 创建处理函数 CREATE FUNCTION dbo.f_strUnite(@id int) RETURNS varchar(8000) AS BEGIN DECLARE @str varchar(8000) SET @str = '' SELECT @str = @str + ',' + value FROM tb WHERE id=@id RETURN STUFF(@str, 1, 1, '') END GO -- 调用函数 SELECt id, value = dbo.f_strUnite(id) FROM tb GROUP BY id drop table tb drop function dbo.f_strUnite go /* id value ----------- ----------- 1 aa,bb 2 aaa,bbb,ccc (所影响的行数为 2 行) */ --=================================================================================== 2. 新的解决方法(在sql server 2005中用OUTER APPLY等解决。) create table tb(id int, value varchar(10)) insert into tb values(1, 'aa') insert into tb values(1, 'bb') insert into tb values(2, 'aaa') insert into tb values(2, 'bbb') insert into tb values(2, 'ccc') go -- 查询处理 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 drop table tb /* id values ----------- ----------- 1 aa,bb 2 aaa,bbb,ccc (2 行受影响) */ --SQL2005中的方法2 create table tb(id int, value varchar(10)) insert into tb values(1, 'aa') insert into tb values(1, 'bb') insert into tb values(2, 'aaa') insert into tb values(2, 'bbb') insert into tb values(2, 'ccc') go select id, [values]=stuff((select ','+[value] from tb t where id=tb.id for xml path('')), 1, 1, '') from tb group by id /* id values ----------- -------------------- 1 aa,bb 2 aaa,bbb,ccc (2 row(s) affected) */ drop table tb
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---------------------------- -- Author :fredrickhu(小F,向高手学习) -- Date :2011-12-22 21:15:35 -- Version: -- Microsoft SQL Server 2008 (RTM) - 10.0.1600.22 (Intel X86) -- Jul 9 2008 14:43:34 -- Copyright (c) 1988-2008 Microsoft Corporation -- Enterprise Evaluation Edition on Windows NT 5.1 <X86> (Build 2600: Service Pack 3) -- ---------------------------- --> 测试数据:[TABLE1] if object_id('[TABLE1]') is not null drop table [TABLE1] go create table [TABLE1]([ID] int,[MACHINE] varchar(5)) insert [TABLE1] select 1,'A-001' union all select 1,'A-002' union all select 2,'A-003' union all select 2,'A-004' union all select 3,'A-005' --> 测试数据:[TABLE2] if object_id('[TABLE2]') is not null drop table [TABLE2] go create table [TABLE2]([key] int) insert [TABLE2] select 1 union all select 2 union all select 3 --------------开始查询-------------------------- select id, [MACHINE]=stuff((select ','+[MACHINE] from TABLE1 a join TABLE2 b on a.id=b.[key] where a.id=t.id for xml path('')), 1, 1, '') from TABLE1 t group by id