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Re: A plea for peace. was: RE: DAML+OIL (March 2001) released: a correction

From: Jonathan Borden <jborden@mediaone.net>
Date: Thu, 5 Apr 2001 16:37:23 -0400
Message-ID: <038901c0be10$3919cc00$0a2e249b@nemc.org>
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
Cc: <phayes@ai.uwf.edu>, <www-rdf-logic@w3.org>
Peter F. Patel-Schneider wrote:

> From: "Jonathan Borden" <jborden@mediaone.net>
>
...
>
> > I suppose I've always seen as one of the benefits of RDF's triple model
the
> > very fact that it maps so easily onto a relational table -- and admit
that I
> > assumed this abstract syntax would in some sense inherit the formalism
of
> > the underlying database (e.g. this very relational model you mention).
If
> > you say this _isn't_ the case then I certainly agree things need to be
> > fixed, it just seems as though it shouldn't be that hard to do.
>
> I would be very interested in hearing about the details of this easy
> mapping.  (Yes, you should consider me to be very skeptical about this.)
> I see a number of mismatches between the RDB model and the RDF model,
> including open-world versus closed-world, finite versus infinite domains,
> notions of identity, how to handle URIs and the things they refer to,
> reification, transitivity, inference of types, typing (particularly
> subtyping), and domain and range.
>

Part of the issue is that you are mixing up RDF Schema (e.g. domain, range)
with RDF... For RDF alone:

DEFINE TABLE triples AS
    predicate : URI
    subject : URI
    object : URI

-- note that RDF literals can be encoded as "an example": data:text/plain,an
example so that all objects can be represented as URIs, literals using the
"data:" scheme.

-- a URI is a string having the syntax described in RFC 2396 (the EBNF isn't
quite perfect but close enough)

Let's start with this alone, and add concepts only as absolutely needed.

-Jonathan
Received on Thursday, 5 April 2001 16:52:58 GMT

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