Returning both raise_application_error and return value from db function...

Question

Hi ,
I use Oracle 10g and forms10g.
I have written a db packaged function such as:
function fnc_ipologismos_xiliometron(code_poleis_apo_var in varchar2,code_poleis_pros_var in varchar2)
   return number
   is
    apostasi_var ref_apostaseis_poleon.apostasi%type;
    onomasia_pol_apo_var ref_poleis.onomasia%type;
    onomasia_pol_pros_var ref_poleis.onomasia%type;
    begin
     begin
        select onomasia into onomasia_pol_apo_var
          from ref_poleis
          where code_poleis=code_poleis_apo_var;
     end;
     begin
        select onomasia into onomasia_pol_pros_var
          from ref_poleis
          where code_poleis=code_poleis_pros_var;
     end;
     begin
      select apostasi into apostasi_var
       from ref_apostaseis_poleon
       where code_poleis_apo=code_poleis_apo_var and code_poleis_pros=code_poleis_pros_var;
      exception
       when no_data_found
then
apostasi_var:=0;
return apostasi_var;
raise_application_error(-20015,'a message');
--return apostasi_var;
end;      return apostasi_var;
    end;The problem is that when the exception written above (in bold) returns 0 and exits the function.... whereas i want this value to be returned as well as the message in the raise_application_error....
I call this function in WHEN-VALIDATE-ITEM of a block item... such as:
if pkg_mod3_general.fnc_ipologismos_xiliometron
(:mod3_entoli_metakinisis.code_poleis_apo_type_id,:mod3_entoli_metakinisis.code_poleis_type_id)=0
              and :mod3_entoli_metakinisis.seq_code_meso_metakin_type_id=2
              then
                raise form_trigger_failure;
  end if;     When the above condition is true then no message is displayed and the cursor sticks to the item(as the raise_application_error in the db packaged function is after the exit of the function) and when the condition is false then no message is displayed again ... as expected.....
How is it get the desired result.....- get the message from the raise_application_error and the function returns 0.....?????
Many thanks,
Simon

Answer 1

you cannot RETURN and RAISE a function.
RETURN ends the function immediately
RAISE ends the program unit and jumps in the EXCEPTION-Handler, if it exists. Else the function ends