ORA-22950 cannot ORDER objects without MAP or ORDER method

Question

Hello
I'm receiving the above error message at the BULK COLLECT point. I've pasted all relevant code below - any help much appreciated. This has got me stumped....
Thanks in advance
Tim
create or replace type PROG_MEDIA_TYP as object
(episode_id number,
house_number varchar2))
create or replace type t_all_prog_medias as TABLE of PROG_MEDIA_TYP
v_All_Prog_Media t_All_Prog_Medias ;
SELECT DISTINCT Prog_Media_Typ(Pm.Episode_Id,
Substr(Pm.House_Number, 1, 8)) BULK COLLECT
INTO v_All_Prog_Media
FROM Prog_Media Pm;

Answer 1

This has to do with your "distinct" keyword. If you don't use distinct, everything is OK, but if you want to use distinct, you have to tell, HOW Oracle can distinguish between two "object members".
First, we just select any record with bulk collect:
SQL> create or replace type emp_media_type
  2    as object (
  3      empno    number,
  4      ename    varchar2(30)
  5    )
  6  /
Type created.
SQL> create or replace type t_emp_media_type as table of emp_media_type;
  2  /
Type created.
SQL> get t
  1  declare
  2    l_all_emp_media_type    t_emp_media_type;
  3  begin
  4    select emp_media_type(empno, ename)
  5    bulk collect into l_all_emp_media_type
  6    from   emp;
  7* end;
SQL> /
PL/SQL procedure successfully completed.This is working nicely. But if we want to have only distinct records, we first have to tell Oracle, how this distinction can be made. That is where the ORDER function comes into play.
SQL> drop type t_emp_media_type;
Type dropped.
SQL> get tt
  1  create or replace type emp_media_type
  2    as object (
  3      empno    number,
  4      ename    varchar2(30),
  5      order member function sortorder(p_emp emp_media_type) return number
      -- this is now the order function to tell Oracle how two objects can be ordered
  6*   )
SQL> /
Type created.
SQL> get type2.sql
  1  create or replace type body emp_media_type as
  2    order member function sortorder(p_emp emp_media_type) return number is
  3    begin
  4      if p_emp.empno < empno then
  5        return 1;
  6      elsif p_emp.empno > empno then
  7        return -1;
  8      else
  9        return 0;
10      end if;
11    end;
12* end;
SQL> /
Type body created.
SQL> create or replace type t_emp_media_type as table of emp_media_type;
  2  /
Type created.
SQL> get t
  1  declare
  2    l_all_emp_media_type    t_emp_media_type;
  3  begin
  4    select distinct emp_media_type(empno, ename)
  5    bulk collect into l_all_emp_media_type
  6    from   emp;
  7* end;
SQL> /
PL/SQL procedure successfully completed.
SQL> You see how nicely it works once you have the order function defined?