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') goCREATE 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 iddrop 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 tbdrop 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') goselect 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
Create table tt ( id int, strs varchar(50) ) Create table #tt ( id int, strs varchar(50) ) --drop table tt --drop table #tt insert into tt values(1,'a') insert into tt values(1,'b') insert into tt values(1,'a') insert into tt values(2,'c') insert into tt values(2,'d') insert into tt values(2,'a') insert into tt values(3,'e') declare @id int , @str varchar(1000) declare my_cursor cursor for select id from tt open my_cursor fetch my_cursor into @id while @@FETCH_STATUS = 0 begin set @str='' SELECT @str = @str +cast(isnull(strs+',','') as varchar)+' ' from tt where id=@id set @str=left(@str,len(@str)-1) insert into #tt select @id,@str fetch my_cursor into @id END close my_cursor deallocate my_cursorselect distinct * from #tt
create table #t ( id int, str1 varchar(20) )INSERT INTO #t SELECT 1,'a' INSERT INTO #t SELECT 1,'b' INSERT INTO #t SELECT 1,'a' INSERT INTO #t SELECT 2,'c' INSERT INTO #t SELECT 2,'d' INSERT INTO #t SELECT 2,'a' INSERT INTO #t SELECT 3,'e'select id,str1=stuff((select ','+str1 from #t a where a.id=b.id for xml path('')),1,1,'') from #t b group by id
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')
goCREATE 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 iddrop 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 tbdrop 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')
goselect 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
Create table tt
(
id int,
strs varchar(50)
)
Create table #tt
(
id int,
strs varchar(50)
)
--drop table tt
--drop table #tt
insert into tt values(1,'a')
insert into tt values(1,'b')
insert into tt values(1,'a')
insert into tt values(2,'c')
insert into tt values(2,'d')
insert into tt values(2,'a')
insert into tt values(3,'e')
declare @id int , @str varchar(1000)
declare my_cursor cursor for
select id from tt
open my_cursor
fetch my_cursor into @id
while @@FETCH_STATUS = 0
begin
set @str=''
SELECT @str = @str +cast(isnull(strs+',','') as varchar)+' ' from tt where id=@id
set @str=left(@str,len(@str)-1)
insert into #tt
select @id,@str
fetch my_cursor into @id
END
close my_cursor
deallocate my_cursorselect distinct * from #tt
create table #t
(
id int,
str1 varchar(20)
)INSERT INTO #t SELECT 1,'a'
INSERT INTO #t SELECT 1,'b'
INSERT INTO #t SELECT 1,'a'
INSERT INTO #t SELECT 2,'c'
INSERT INTO #t SELECT 2,'d'
INSERT INTO #t SELECT 2,'a'
INSERT INTO #t SELECT 3,'e'select id,str1=stuff((select ','+str1 from #t a where a.id=b.id for xml path('')),1,1,'') from #t b group by id