--- In firebird-support@yahoogroups.com, Allysson Costa
<allcostaes@...> wrote:

>
> I found a common solution to previous problem.
>
> But I don't know how to use it.
>
> Then, my question is:
> What is correct way to use "IF UPDATE(colunm)" function inside

trigger.

Any version:

IF ((OLD.COLUMN <> NEW.COLUMN) OR
(OLD.COLUMN IS NULL AND NEW.COLUMN IS NOT NULL) OR
(OLD.COLUMN IS NOT NULL AND NEW.COLUMN IS NULL)) THEN ...

Firebird 2 or newer:

IF (OLD.COLUMN IS DISTINCT FROM NEW.COLUMN) THEN ...

Adam