oracle 怎样实现合并相同行 希望是 一条语句

[ggyyss_001]

oracle 怎样实现合并相同行 希望是一条语句
如
create table tb
(
id number,
name varchar2(100)
);
insert into tb values(1,'aa');
insert into tb values(2,'bb');
insert into tb values(3,'cc');
insert into tb values(1,'dd');
insert into tb values(1,'ee');

实现
1 aa,dd,ee
2 bb
3 cc

[hebo2005]

一条语句不太可能，写个函数或者存储过程可以实现

[codearts]

create or replace function t_f                                                                    
(                                                                               
  v_id number                                                                   
)                                                                               
return varchar2                                                                 
is                                                                              
  result varchar2(5000);                                                        
begin                                                                           
 result := '';                                                                  
 for x in (select name from tb where id = v_id)                                 
 loop                                                                           
     result := result || x.name || ',';                                         
 end loop;                                                                      

 result := substr(result, 1, length(result) - 1);                               
 return result;                                                                 
end t_f;              

select id, t_f(id) as name from (select distinct id from tb) x