Re: Warning about null and open question to Oracle
Date: 1995/06/23
Message-ID: <RG6-GRa.rrutt_at_delphi.com>#1/1
Kurtis D. Rader <krader_at_sequent.com> writes:
>John Jones <john_at_iluvatar.tip.duke.edu> writes:
>>just think that NOTHING should be equal to NOTHING. I have heard that
>>other databases do this and was really just sounding off hoping Oracle
>>would do the same. Oh well, can't have everything I guess. Thanks for
>>listening.
>
>The problem, however, is that NULL does not mean "nothing", NULL
>means "unknown". And if two values are unknown you can't know if
The real PROBLEM here is that Oracle decided long ago that, for text strings,
"nothing" is the same as "unknown". They treat a zero-length string as
NULL, and that causes they major headaches.
-
However, I suspect we are stuck with this longstanding screwup, as many
programs have come to expect, and even depend on, this ugly fact.
-
Fortunately, the Oracle database does distinguish the numeric value zero
from the "unknown" value NULL.
- Rick --
(Rick Rutt is a system architect living and working in Midland, Michigan.) Received on Fri Jun 23 1995 - 00:00:00 CEST