Re: So what's null then if it's not nothing?
Date: Tue, 29 Nov 2005 13:51:45 GMT
Message-ID: <R1Zif.6702$N45.1120_at_newsread1.news.atl.earthlink.net>
"Frank Hamersley" <terabitemightbe_at_bigpond.com> wrote in message
news:cBYif.6655$ea6.2147_at_news-server.bigpond.net.au...
> David Cressey wrote:
>
> > Oracle chose to indicate a null by the "impossible values" method. For
> > example, A NULL in a NUMBER is represented by minus zero. A single
zero
> > byte is used to represent a NULL in a VARCHAR. Unfortunately, an empty
> > string, having length zero, gets the same representation. Oops!
> >
> > I don't know about Sybase.
>
> On zip research I am guessing the "impossible values" method given their
> propensity to force '' to ' ' to avoid embarassment and confusion.
Then again, maybe they got their model for "missing values" from Pick!
(ducking) Received on Tue Nov 29 2005 - 14:51:45 CET