> Yes You're right at the begining, my procedure was like your sentence
>
> UPDATE Cari Set Borc = BORC + :YOURVALUE where CariID = :CariID;
>
> but if the field borc have null value the result doesn't change again
> NULL

Ups - you're right.

>
> I'll try to remove allow null property for the fields that I would
> make this kind of calculations.

Just add a before insert (maybe also update) trigger and set the value
to 0 if it is null.

> thanks for your interest..

you're welcome.

luc.