有人能将下面的sql语句转到oracle里执行吗
create   function   fun(@userid   varchar(200))
returns   varchar(2000)
as
begin
declare   @re   varchar(2000)
set   @re= ' '
select   @re=@re+ ', '+username   from   userinfo
where   charindex(userid,   @userid)> 0

return(stuff(@re,   1,   1,   ' '))
end

select   meetingid,     meetingname,  
createrid=dbo.fun(createrid),
joinid=dbo.fun(joinid)
from   meetinginfo


------解决方案--------------------
create or replace function fun(p_userid varchar2)
returns varchar2(2000)
is
v_re varchar2(2000);
begin
p_re:= ' ';
select v_re|| ', '|| username into v_re from userinfo
where instr(userid, p_userid)> 0;

return substr(v_re,2,length(v_re)-1);
end;

------解决方案--------------------
select meetingid,meetingname,
fun(createrid) as createrid ,
fun(joinid) as joinid
from meetinginfo