Re: The Theoretical Foundations of the Relational Model
Date: 24 Jun 2002 18:35:46 +0200
Message-ID: <3d174a62$1_at_news.uia.ac.be>
In article <3d1736a2.2083746_at_news.verizon.net>,
JRStern <JXSternChangeX2R_at_gte.net> wrote:
>
>What we have here is a sign that in doing something with the database, we
>may be doing something which is not entirely equivalent to predicate logic.
>In some cases, the "easy" way to do stuff would be to specify a logical or
>physical order as part of the data model (of views, perhaps of tables).
Er, a "physical order" in a logical/conceptual data model is an oxymoron.
Easy for the user, sure, and defining such a data model is not difficult at
all. But can you give me a sound and complete axiomatization for this new
type of logic? Can you give me a reasonably complete set of algebraic
- Jan Hidders