> > Null and nil are different beasts, please don't confuse'em.
>
> How are they different? Except that interbase doesn't understand the
> word NIL but does NULL?
>
> They can mean the same thing, depending on what language you use them
> in.
>
> SQL: NULL=absence of value
> Delphi: nil=pointer to zero
> Javascript: null=no object
> C: null=just about anything you like

Do not be confused by word NULL.
SQL NULL is _not_ absence of value; rather it means _unknown_ value.
It is a state that means "there could be _any_ value, but we do not know which it is".
It is even more fuzzy than uninitialized pointer.

Ivan
prenosil@...
http://www.volny.cz/iprenosil/interbase