求助

[孤舟风雨]

表一：
id name
1 aa
2 bb
表二：
Tid Tname
1 测试
1 评论
1 测试1
2 DD
2 DC
2 BD
查询出来的结果是：
id name Tname
1 aa 测试,评论，测试1
2 bb DD,DC,BD

[AcHerat]

select *,stuff((select ','+tname from tb2 where id = t.id for xml path('')),1,1,'') as tname
from tb1 t
group by id,name

[百年树人]

if object_id('[t1]') is not null drop table [t1]
go
create table [t1]([id] int,[name] varchar(2))
insert [t1]
select 1,'aa' union all
select 2,'bb'
if object_id('[t2]') is not null drop table [t2]
go
create table [t2]([Tid] int,[Tname] varchar(5))
insert [t2]
select 1,'测试' union all
select 1,'评论' union all
select 1,'测试1' union all
select 2,'DD' union all
select 2,'DC' union all
select 2,'BD'

select a.id,a.name,
Tname=stuff((select ','+tname from t2 where tid=a.id for xml path('')),1,1,'')
from t1 a
group by a.id,a.name

/**
id          name Tname
----------- ---- ----------------------
1           aa   测试,评论,测试1
2           bb   DD,DC,BD

(2 行受影响)
**/

[叶子]

--合并列值
--原著：邹建
--改编：爱新觉罗.毓华(十八年风雨,守得冰山雪莲花开)  2007-12-16  广东深圳

--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。) 
--1. 创建处理函数
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 

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, value = dbo.f_str(id) FROM tb GROUP BY id 

drop table tb 
drop function dbo.f_str 

/* 
id          value      
----------- ----------- 
1          aa,bb 
2          aaa,bbb,ccc 
（所影响的行数为2 行）
*/ 

--2、另外一种函数. 
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 

--创建一个合并的函数
create function f_hb(@id int) 
returns varchar(8000) 
as 
begin 
  declare @str varchar(8000) 
  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 

--调用自定义函数得到结果：
select distinct id ,dbo.f_hb(id) as value from tb 

drop table tb 
drop function dbo.f_hb 

/* 
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
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

[唐诗三百首]

create table tab1
(id int, name char(5))

insert into tab1
select 1, 'aa' union all
select 2, 'bb'

create table tab2
(Tid int, Tname varchar(6))

insert into tab2
select 1, '测试' union all
select 1, '评论' union all
select 1, '测试1' union all
select 2, 'DD' union all
select 2, 'DC' union all
select 2, 'BD'


select a.id,a.name,
left(b.Tname2,len(b.Tname2)-1) 'Tname'
from tab1 a
inner join (
select t2.Tid,
cast((select Tname+',' from tab2 t3 where t3.Tid=t2.Tid for xml path(''))
as varchar) Tname2
from tab2 t2 group by t2.Tid) b
on a.id=b.Tid

id          name  Tname
----------- ----- ------------------------------
1           aa    测试,评论,测试1
2           bb    DD,DC,BD

(2 row(s) affected)

[勿勿]

--表一：
--id name
--1 aa
--2 bb
--表二：
--Tid Tname
--1 测试
--1 评论
--1 测试1
--2 DD
--2 DC
--2 BD


if OBJECT_ID('aa') is not null
 drop table aa
  go 
create table aa (id int,name varchar(50))
insert into aa values(1,'aa')
insert into aa values(2,'bb')

if OBJECT_ID('bb') is not null
 drop table bb
  go 
create table bb (Tid int,Tname varchar(50))
insert into bb values(1,'测试')
insert into bb values(1,'评论')
insert into bb values(1,'测试1')
insert into bb values(2,'DD')
insert into bb values(2,'DD')
insert into bb values(2,'BD')
--查询出来的结果是：
--id name  Tname
--1  aa    测试,评论，测试1
--2   bb   DD,DC,BD
 

select a.id,a.name ,
      stuff((select ',' + Tname from bb where  Tid=a.id    for  xml path ('')), 1,1,'') as 测试1 from aa  a
 group by a.id,a.name
 
 

id          name                                               测试1
----------- -------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1           aa                                                 测试,评论,测试1
2           bb                                                 DD,DD,BD

(2 行受影响)