Problem calling program unit function in Forms 6i

Question

Hi,
I'm new to programming with Oracle Forms. I have a question that I cannot seem to figure out. In Forms 6i, I have created a program unit function that compiles correctly. The trouble I'm having is calling it and displaying the function's contents into a non-database display item I created. When I run my app, the display item it blank while my other fields populate.
I first tried to call it in a POST-QUERY trigger but I get an error stating "function cannot be called in SQL." Can you not call a function in a form's trigger? If so, what would be the correct syntax?
Then I tried to call it in the non-database item's Calculation => Formula (property) by just stating the function_name(parameter). This appears to compile fine too, but still no display at runtime.
What would be the best way to reference my function to display its contents properly? Does anyone have any examples? Any help would be greatly appreciated. Thank you.

Answer 1

First, get rid of the
EXCEPTION WHEN NO_DATA_FOUND
in your function. Summary queries never raise no_data_found; They just return null.
Your ":history.consecutive_years := NumberOfYears(:student.id);" is the proper way to call the function. That is what I was trying to tell you with the example: ':Myblock.Item_x := function_name(some_parm);' code
If your post-query trigger only executes the function, then I think your problem is somewhere else:
'FRM-40735 POST-QUERY trigger raised unhandled exception' looks like a problem elsewhere.
Don't know of a good website. Just keep asking here -- somebody is bound to pop in and help you out.
One more thing: drop this into your form-level on-error trigger. It often helps to find problems:
-- On-error form-level trigger                                       --*
DECLARE
  Err_Code NUMBER(5)     := ERROR_CODE;
  Err_Text VARCHAR2(100) := ERROR_TEXT;
  MSG      VARCHAR2(150)
          := SUBSTR('   '||ERROR_TYPE||'-'||TO_CHAR(Err_Code)||': '
                                     ||Err_Text,1,150);
  DBMS_TXT VARCHAR2(500);
BEGIN
  IF Err_Code IN (40401,40405,     --No changes to save/apply
                  40100,40352) THEN --at first/last record
    MESSAGE(MSG,NO_ACKNOWLEDGE); -- Don't raise Form_Trigger_Failure
  ELSE -- all other messages
    -- check database error message --
    DBMS_TXT := SUBSTR(DBMS_ERROR_TEXT,1,500);
    if  DBMS_TXT is not null
    and substr(DBMS_TXT,5,5)
      not in('00000',
             '01403') then --1403=no data found
      -- show entire msg, add new_line chars.
      DBMS_TXT := replace(DBMS_TXT,'ORA-',chr(10)||'ORA-');
      DBMS_TXT := replace(DBMS_TXT,' '||chr(10), chr(10));
      -- show MSG and DBMS_TXT both as an alert --
      --PLL_ALERT( ltrim(MSG) || DBMS_TXT );
      Message(ltrim(MSG) || DBMS_TXT );
      Message(' ',no_acknowledge);
      Raise Form_Trigger_Failure;
    else
      Message(MSG);
      Message(' ',no_acknowledge);
      Raise Form_Trigger_Failure;
    End if;
  END IF;
END; -- end of on-error trigger