字符串聚合问题，难！

SQL code问题描述：
无论是在sql 2000，还是在 sql 2005 中,都没有提供字符串的聚合函数，
  所以，当我们在处理下列要求时，会比较麻烦：
有表tb, 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-- 1. 创建处理函数
CREATE FUNCTION dbo.f_str(@id int)
RETURNS varchar(8000)
AS
BEGIN
    DECLARE @r varchar(8000)
    SET @r = ''
    SELECT @r = @r + ',' + value
    FROM tb
    WHERE id=@id
    RETURN STUFF(@r, 1, 1, '')
END
GO
-- 调用函数SELECt id, values=dbo.f_str(id)
FROM tb
GROUP BY id-- 2. 新的解决方法
-- 示例数据
DECLARE @t TABLE(id int, value varchar(10))
INSERT @t SELECT 1, 'aa'
UNION ALL SELECT 1, 'bb'
UNION ALL SELECT 2, 'aaa'
UNION ALL SELECT 2, 'bbb'
UNION ALL SELECT 2, 'ccc'-- 查询处理
SELECT *
FROM(
    SELECT DISTINCT
        id
    FROM @t
)A
OUTER APPLY(
    SELECT
        [values]= STUFF(REPLACE(REPLACE(
            (
                SELECT value FROM @t N
                WHERE id = A.id
                FOR XML AUTO
            ), '<N value="', ','), '"/>', ''), 1, 1, '')
)N/*--结果
id          values
----------- ----------------
1           aa,bb
2           aaa,bbb,ccc
(2 行受影响)
--*/--各种字符串分函数--3.3.1 使用游标法进行字符串合并处理的示例。
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3--合并处理
--定义结果集表变量
DECLARE @t TABLE(col1 varchar(10),col2 varchar(100))--定义游标并进行合并处理
DECLARE tb CURSOR LOCAL
FOR
SELECT col1,col2 FROM tb ORDER BY  col1,col2
DECLARE @col1_old varchar(10),@col1 varchar(10),@col2 int,@s varchar(100)
OPEN tb
FETCH tb INTO @col1,@col2
SELECT @col1_old=@col1,@s=''
WHILE @@FETCH_STATUS=0
BEGIN
    IF @col1=@col1_old
        SELECT @s=@s+','+CAST(@col2 as varchar)
    ELSE
    BEGIN
        INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
        SELECT @s=','+CAST(@col2 as varchar),@col1_old=@col1
    END
    FETCH tb INTO @col1,@col2
END
INSERT @t VALUES(@col1_old,STUFF(@s,1,1,''))
CLOSE tb
DEALLOCATE tb
--显示结果并删除测试数据
SELECT * FROM @t
DROP TABLE tb
/*--结果
col1       col2
---------- -----------
a          1,2
b          1,2,3
--*/
GO
/*==============================================*/
--3.3.2 使用用户定义函数，配合SELECT处理完成字符串合并处理的示例
--处理的数据
CREATE TABLE tb(col1 varchar(10),col2 int)
INSERT tb SELECT 'a',1
UNION ALL SELECT 'a',2
UNION ALL SELECT 'b',1
UNION ALL SELECT 'b',2
UNION ALL SELECT 'b',3
GO--合并处理函数
CREATE FUNCTION dbo.f_str(@col1 varchar(10))
RETURNS varchar(100)
AS
BEGIN
    DECLARE @re varchar(100)
    SET @re=''
    SELECT @re=@re+','+CAST(col2 as varchar)
    FROM tb
    WHERE col1=@col1
    RETURN(STUFF(@re,1,1,''))
END
GO--调用函数
SELECT col1,col2=dbo.f_str(col1) FROM tb GROUP BY col1
--删除测试
DROP TABLE tb
DROP FUNCTION f_str
/*--结果
col1       col2
---------- -----------
a          1,2
b          1,2,3
--*/
GO/*==============================================*/参考

/*
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)
愿和大家共同进步
如有雷同、实属巧合
●●●●●2009-09-04 15:19:28.123●●●●●
　★★★★★soft_wsx★★★★★
*/
if object_ID('TB') IS NOT NULL DROP TABLE TB
  create table tb(id int,corpname varchar(10),salebrand varchar(10))
insert tb
          select 1,  '化成公司',  '阿迪'
union all select 2,  '化成公司',  '耐克'
union all select 3,  '化成公司',  '奔驰'
union all select 4,  '天意公司',  '宝马'
union all select 5,  '长空公司',  '奥迪'
go
if object_id('f_tb') is not null drop function f_tb
go
  create function f_tb(@corpname nvarchar(100))
    returns nvarchar(100)
    as
   begin
     declare @sql nvarchar(4000)
     set @sql=N''
     select @sql=@sql+N','+salebrand from tb where corpname=@corpname
     set @sql=stuff(@sql,1,1,N'')
     return(@sql)
   end
goif object_id('f_tb2') is not null drop function f_tb2
go
  create function f_tb2(@corpname nvarchar(100))
    returns nvarchar(100)
    as
   begin
     declare @sql nvarchar(4000)
     set @sql=N''
     select @sql=@sql+N','+cast(id as varchar) from tb where corpname=@corpname
     set @sql=stuff(@sql,1,1,N'')
     return(@sql)
   end
goselect dbo.f_tb2(corpname) as 公司代码,corpname as 公司,dbo.f_tb(corpname) as 经营品牌 from tb
group by corpname

/*
公司代码公司经营品牌
5 长空公司奥迪
1,2,3 化成公司阿迪,耐克,奔驰
4 天意公司宝马
*/try

----------------------------------------------------------------
-- Author  :fredrickhu(我是小F，向高手学习)
-- Date    :2009-09-04 15:18:07
-- Verstion:
--      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,[corpname] varchar(8),[salebrand] varchar(4))
insert [tb]
select 1,'化成公司','阿迪' union all
select 2,'化成公司','耐克' union all
select 3,'化成公司','奔驰' union all
select 4,'天意公司','宝马' union all
select 5,'长空公司','奥迪'
--------------开始查询--------------------------select
  id=stuff((select ','+ltrim([id]) from tb t where corpname=tb.corpname for xml path('')), 1, 1, ''),
  corpname,
  [salebrand]=stuff((select ','+[salebrand] from tb t where corpname=tb.corpname for xml path('')), 1, 1, '')
from
  tb
group by
  corpname
order by
  id
----------------结果----------------------------
/* id                                                                                                                                                                                                                                                               corpname salebrand
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1,2,3                                                                                                                                                                                                                                                            化成公司     阿迪,耐克,奔驰
4                                                                                                                                                                                                                                                                天意公司     宝马
5                                                                                                                                                                                                                                                                长空公司     奥迪(3 行受影响)*/

--2005
DECLARE @TB TABLE(ID INT,CORPNAME VARCHAR(10),SALEBRAND VARCHAR(10))
INSERT INTO @TB
SELECT 1,  '化成公司',  '阿迪'
UNION ALL SELECT 2,  '化成公司' , '耐克'
UNION ALL SELECT 3,  '化成公司' , '奔驰'
UNION ALL SELECT 4,  '天意公司' , '宝马'
UNION ALL SELECT 5 , '长空公司' , '奥迪'
SELECT ID = STUFF((SELECT ','+CAST(ID AS VARCHAR(10)) FROM @TB WHERE A.CORPNAME = CORPNAME FOR XML PATH('')),1,1,''),
       CORPNAME,
       SALEBRAND = STUFF((SELECT ','+CAST(SALEBRAND AS VARCHAR(10)) FROM @TB WHERE A.CORPNAME = CORPNAME FOR XML PATH('')),1,1,'')
FROM @TB A
GROUP BY CORPNAME

/*
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)
愿和大家共同进步
如有雷同、实属巧合
●●●●●2009-09-04 15:19:28.123●●●●●
　★★★★★soft_wsx★★★★★
*/
if object_ID('TB') IS NOT NULL DROP TABLE TB
  create table tb(id int,corpname varchar(10),salebrand varchar(10))
insert tb
          select 1,  '化成公司',  '阿迪'
union all select 2,  '化成公司',  '耐克'
union all select 3,  '化成公司',  '奔驰'
union all select 4,  '天意公司',  '宝马'
union all select 5,  '长空公司',  '奥迪'
go
if object_id('f_tb') is not null drop function f_tb
go
  create function f_tb(@corpname nvarchar(100))
    returns nvarchar(100)
    as
   begin
     declare @sql nvarchar(4000)
     set @sql=N''
     select @sql=@sql+N','+salebrand from tb where corpname=@corpname
     set @sql=stuff(@sql,1,1,N'')
     return(@sql)
   end
goif object_id('f_tb2') is not null drop function f_tb2
go
  create function f_tb2(@corpname nvarchar(100))
    returns nvarchar(100)
    as
   begin
     declare @sql nvarchar(4000)
     set @sql=N''
     select @sql=@sql+N','+cast(id as varchar) from tb where corpname=@corpname
     set @sql=stuff(@sql,1,1,N'')
     return(@sql)
   end
goselect dbo.f_tb2(corpname) as 公司代码,corpname as 公司,dbo.f_tb(corpname) as 经营品牌 from tb
group by corpname
order by 公司代码

/*
公司代码公司经营品牌
1,2,3 化成公司阿迪,耐克,奔驰
4 天意公司宝马
5 长空公司奥迪
*/

/*
公司代码公司经营品牌
5 长空公司奥迪
1,2,3 化成公司阿迪,耐克,奔驰
4 天意公司宝马
*/不好意思，忘记排序了！2000-2008通用！想学新知识看小F的！

/*
标题：按某字段合并字符串之一(简单合并)
作者：爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开)
时间：2008-11-06
地点：广东深圳描述：将如下形式的数据按id字段合并value字段。
id    value
----- ------
1     aa
1     bb
2     aaa
2     bbb
2     ccc
需要得到结果：
id     value
------ -----------
1      aa,bb
2      aaa,bbb,ccc
即：group by id, 求 value 的和（字符串相加）
*/
--1、sql2000中只能用自定义的函数解决
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')
gocreate function dbo.f_str(@id int) returns varchar(100)
as
begin
    declare @str varchar(1000)
    set @str = ''
    select @str = @str + ',' + cast(value as varchar) from tb where id = @id
    set @str = right(@str , len(@str) - 1)
    return @str
end
go--调用函数
select id , value = dbo.f_str(id) from tb group by iddrop function dbo.f_str
drop table tb
--2、sql2005中的方法
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')
goselect id, [value] = stuff((select ',' + [value] from tb t where id = tb.id for xml path('')) , 1 , 1 , '')
from tb
group by iddrop table tb
--3、使用游标合并数据
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
declare @t table(id int,value varchar(100))--定义结果集表变量
--定义游标并进行合并处理
declare my_cursor cursor local for
select id , value from tb
declare @id_old int , @id int , @value varchar(10) , @s varchar(100)
open my_cursor
fetch my_cursor into @id , @value
select @id_old = @id , @s=''
while @@FETCH_STATUS = 0
begin
    if @id = @id_old
       select @s = @s + ',' + cast(@value as varchar)
    else
      begin
        insert @t values(@id_old , stuff(@s,1,1,''))
        select @s = ',' + cast(@value as varchar) , @id_old = @id
      end
    fetch my_cursor into @id , @value
END
insert @t values(@id_old , stuff(@s,1,1,''))
close my_cursor
deallocate my_cursorselect * from @t
drop table tb

--测试数据
declare @tb table(id int,corpname varchar(10),salebrand varchar(10))
insert @tb
          select 1,  '化成公司',  '阿迪'
union all select 2,  '化成公司',  '耐克'
union all select 3,  '化成公司',  '奔驰'
union all select 4,  '天意公司',  '宝马'
union all select 5,  '长空公司',  '奥迪' --合并
select * into # from @tb order by corpname
alter table # alter column id varchar(50)
alter table # alter column salebrand varchar(50)declare @id varchar(50), @salebrand varchar(50), @corpname varchar(10)update # set @id = case when @corpname = corpname then @id + ',' + id else id end, @corpname = corpname, id = @id
update # set @salebrand = case when @corpname = corpname then @salebrand + ',' + salebrand else salebrand end, @corpname = corpname, salebrand = @salebrandselect max(id) as id, corpname, max(salebrand) as salebrand from #
  group by corpname
/*
id                                                 corpname   salebrand
-------------------------------------------------- ---------- --------------------------------------------------
5                                                  长空公司       奥迪
1,2,3                                              化成公司       阿迪,耐克,奔驰
4                                                  天意公司       宝马
*/

忘了order了
select max(id) as id, corpname, max(salebrand) as salebrand from #
group by corpname order by id

--> 生成测试数据表:tbIf not object_id('[tb]') is null
Drop table [tb]
Go
Create table [tb]([id] int,[corpname] nvarchar(4),[salebrand] nvarchar(2))
Insert [tb]
Select 1,N'化成公司',N'阿迪' union all
Select 2,N'化成公司',N'耐克' union all
Select 3,N'化成公司',N'奔驰' union all
Select 4,N'天意公司',N'宝马' union all
Select 5,N'长空公司',N'奥迪'
Go
--Select * from [tb]-->SQL查询如下:
select distinct
id=stuff((select ','+ltrim(id) from tb where [corpname]=t.[corpname] for xml path('')),1,1,''),
[corpname],
[salebrand]=stuff((select ','+[salebrand] from tb where [corpname]=t.[corpname] for xml path('')),1,1,'')
from tb t
/*
id corpname salebrand
1,2,3 化成公司阿迪,耐克,奔驰
4 天意公司宝马
5 长空公司奥迪
*/

字符串合并：http://blog.csdn.net/lihan6415151528/archive/2009/08/10/4431237.aspx

调试易

字符串聚合问题，难！

解决方案 »