Problems with PL/SQL

Question

Hi,
I know that there are much threads for PL/SQL, but I nowhere found an explanation for my problem ... sorry
I have a LOV with years (2002, 2003, 2004, ...). The display value is a number, the return value is an varchar2. If nothing is selected 0 is returned.
Then I have a report that should be filtered depending on the selection if this LOV.
So my code look like this
DECLARe
str_express varchar2(2000);
BEGIN
IF P2_YEAR != '0' THEN
str_express := 'select ... from ... where year = :P2_YEAR';
ELSE
str_express := 'select ... from ... ';
END IF;
return str_express;
END;
But it never is filtered, I always get all rows. If I delete the IF ... THEN ... ELSE ... END IF; then everything is ok. What have I done wrong? I've also tried
F :P2_YEAR <> '0' ...',
F :P2_YEAR <> 0 ...',
F :P2_YEAR != 0 ...', but nothing works. If I have a look in session state the value of this fields is the selected one and it also works in the select statement without the IF.
Thanks for help.
chrissy

Answer 1

I think the problem is that you are trying to compare a date value to a string in your PL/SQL, try something like this:
if to_char(:P_Year,'YYYY') !='2004'