请问一个SQL语句的写法,很有难度的

drop table t
create table t(id int identity,name varchar(5),class varchar(4))
insert t select '张三','武汉'
union select '李四','武汉'
union select '刘八','武汉'
union select '周九','成都'
union select '蔡十','成都'
union select '何九','北京'
union select '刘小','北京'

drop function fun_t
create function fun_t(@class varchar(10))
returns varchar(2000)
as
begin
declare @a varchar(2000)
set @a=''
select @a=@a+','+cast(name as varchar) from t where class=@class
set @a=right(@a,len(@a)-1)
return @a
end
select distinct class,dbo.fun_t(class) as 连接 from t

[此贴子已经被作者于2007-1-4 15:19:49编辑过]