--字符串分拆处理代码
CREATE FUNCTION f_splitSTR(
@s     varchar(8000),  --待分拆的字符串
@split  varchar(10)     --数据分隔符
)RETURNS TABLE
AS
--SELECT TOP 8000 ID=IDENTITY(int,1,1) INTO dbo.tb_splitSTR  --字符串分拆函数要用到的辅助表.
--FROM syscolumns a,syscolumns b

RETURN(
 SELECT col=CAST(SUBSTRING(@s,ID,CHARINDEX(@split,@s+@split,ID)-ID) as varchar(100))
 FROM tb_splitSTR
 WHERE ID<=LEN(@s+'a')
  AND CHARINDEX(@split,@split+@s,ID)=ID)
--drop table tb_splitSTR
GO

/* --利用以上函数，对某一表的字符串字段字符分拆处理代码
declare @id int,@c varchar(50)
declare k cursor for select * from id_f --字符串待分拆原始表(id int,c varchar(50))
open k
fetch next from k into @id,@c
while (@@fetch_status=0)
 begin
   insert into id_yf --分拆结果表(id int,c varchar(50))
   select @id as id,c.* from f_splitSTR(@c,',') as c
   fetch next from k into @id,@c
 end
close k
deallocate k
*/
--------------------------------------------------------------------------
--字符串合并处理代码
declare @s varchar(300)
set @s=''
SELECT @s=@s+c+','
FROM [dbo].[id_h] --字符串待合并表[id int,c varchar(50)]
where id <> (select top 1 id from id_h order by id desc) order by id

select @s=@s+ c from id_h where id =(select top 1 id from id_h order by id desc)
select @s