Roberto,
> > Another problem is in creating function...
> > How can i create a function that accept and return any type. the type
> > "any" is not allowing as parameter or return type. Is it possible? i want
> > to create a function similar to NULLIF().
>
> Use the standard coalesce().
NULLIF is the converse of COALESCE().
Any idea when you're going to overhaul the CookBook?
--
Josh Berkus
Aglio Database Solutions
San Francisco