--- In firebird-support@yahoogroups.com, Jonathan Neve <jonathan@m...>
wrote:

> Martijn Tonies wrote:
>
> >You're answering your own question: '' (empty string) is NOT NULL.
> >NULL is NULL (empty). An empty string is a value. NULL is a state,
> >so is "NOT NULL".
> >
> IMHO, this unique feature could nearly be considered a bug...

In SQL standard? ;)

Best regards,
Alexander.