ORA-6502: value or numeric error

Question

Hi all,
First off all, I am not very good in PL/SQL so please bear with me:
I have a trigger on a table on after update event. Sample code of the trigger:
create or replace trigger t1
on table1
after update of col1
for each row
begin
for inx in varray1.first .. varray1.last
loop
do something;
end loop;
end;
This trigger throws an error saying "ORA-6502: value or numeric error" if I am trying to update anything into that table but the same trigger works fine when I remove "FOR EACH ROW" statement from the trigger. There is absolutely no change except removal of FOR EACH ROW clause.
I am unable to figure out why. Do anybody?
Thanks in adnvace.

Answer 1

Thanks a lot to all of you for taking time to answer my question.
Again, let me rephrase my question in one single line:
bold Why does the trigger without FOR EACH ROW works and doesnt work with FOR EACH ROW?
What I am guessing is , it might be because of the array what we are using inside the trigger. But its just a guess. One more thing to note here, same code with and without FOR EACH ROW works when I am not using any arrays inside the trigger and thats what is the question. WHY cant same code works when used with FOR EACH ROW when arrays are used inside the trigger.
I am not requesting anybody to write code for me or rectify the problems in the code. All I am interested in is the reason of trigger not working with FOR EACH ROW when arrays are used inside the trigger.
Thanks