Date exception for ora-01839 in my procedure

Question

Hi All!
I am writing a new procedure for validation of date. There I mentioned like below.
select to_date(v_attrValue, 'yyyymmdd') into v_date from dual;
if sql%rowcount<=0 then
gnvPrdError.raiseErrorMsg(gnvInvalidEventDate,
'gnvInvalidEventDate');
end if;
It is raising oracle exception. I would like to catch that exception and thru in my format so that the calling procedure should raise exception.
Please help me on this.
Thanks in advance.
Jai

Answer 1

Paul's solution of having a function that just returns 0 or 1 is an option. Having a WHEN OTHERS clause means that you'll catch every possible exception. Alternately, you could add separate exception handlers for the exceptions you actually expect to get, i.e.
DECLARE
  exc1 exception;
  pragma exception_init( exc1, -1830 );
  exc2 exception;
  pragma exception_init( exc2, -1847 );
BEGIN
  dt := to_date( <<string>>, <<format mask>> )
EXCEPTION
  WHEN exc1 THEN
    <<do something>>
  WHEN exc2 THEN
    <<something else>>
  WHEN exc3 THEN
    <<something else>>
END;Whether you should use a WHEN OTHERS or explicitly declare and catch individual exceptions depends on whether you want to do something different depending on the exception and how comfortable you are enumerating the "valid" exceptions vs. having a catch-all that might catch too much. Personally, I tend to prefer the explicit exceptions approach for production code.
Justin