Re: Implementation of boolean types.
From: Anne & Lynn Wheeler <lynn_at_garlic.com>
Date: 14 Jul 2005 07:38:41 -0600
Message-ID: <m38y091p9a.fsf_at_lhwlinux.garlic.com>
Date: 14 Jul 2005 07:38:41 -0600
Message-ID: <m38y091p9a.fsf_at_lhwlinux.garlic.com>
Jonathan Leffler <jleffler_at_earthlink.net> writes:
> SQL-1999 and SQL-2003 both have a BOOLEAN type, with recognized values
> TRUE, FALSE and UNKNOWN. I'm not clear whether NULL is equivalent to
> UNKNOWN or not; I've not scrutinized the weasel-words carefully enough.
old 3-value logic posting
http://www.garlic.com/~lynn/2003g.html#40 How to cope with missing values - NULLS?
http://www.garlic.com/~lynn/2004l.html#75 NULL
reference to Dec. '92, article by CJ Date
-- Anne & Lynn Wheeler | http://www.garlic.com/~lynn/Received on Thu Jul 14 2005 - 15:38:41 CEST