Re: relations aren't types?
Date: Tue, 30 Dec 2003 07:41:37 GMT
Message-ID: <R_9Ib.11658$lo3.10578_at_newsread2.news.pas.earthlink.net>
Marshall Spight wrote:
> "Lauri Pietarinen" <lauri.pietarinen_at_atbusiness.com> wrote:
>> My understanding is that in the scope of relational databases,
>> atomicity is defined in terms of whether the relational operators
>> can "see" the value or not without the help of "non-relational",
>> or scalar operators.
>
> Interesting. I wonder if that's definition Bob is using, thus causing
> our disconnect about atomicity. Where did you get this definition,
> may I ask?
Obviously, I can't answer for Lauri, but...
It strikes me as being a good statement of an atomic type, and one that can be derived from the writings of Date (and Darwen). I've not seen it in quite that form before - which might mean Lauri has found a new way of stating what atomicity means, or it might mean I've not read the relevant book or paper.
-- Jonathan Leffler #include <disclaimer.h> Email: jleffler_at_earthlink.net, jleffler_at_us.ibm.com Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/Received on Tue Dec 30 2003 - 08:41:37 CET