Re: NULLs: theoretical problems?

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Sat, 18 Aug 2007 08:55:49 -0300
Message-ID: <46c6de02$0$4031$9a566e8b@news.aliant.net>

David Cressey wrote:

> "David Portas" <REMOVE_BEFORE_REPLYING_dportas_at_acm.org> wrote in message
> news:l_Cdnbfs5KQfllvbRVnytgA_at_giganews.com...
>

>>"David Cressey" <cressey73_at_verizon.net> wrote in message
>>news:UGmxi.11$dz3.4_at_trndny01...

>>SELECT DISTINCT i FROM t WHERE x = x;
>>
>>The result is clearly wrong if a null means "x is unknown" or "x is out of
>>range" and possibly wrong if null means "x does not apply".

>
> But if a null means "x is not present" and nothing more, the result is
> clearly right.

I disagree completely. The fact than anyone can disagree makes it anything but clear. Received on Sat Aug 18 2007 - 06:55:49 CDT