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Re: Syntax vs Semantics vs XML Schema vs RDF Schema vs QNames vs URIs (was RE: Using urn:publicid: for namespaces)

From: Thomas B. Passin <tpassin@home.com>
Date: Tue, 21 Aug 2001 09:14:45 -0400
Message-ID: <001601c12a43$3f9e5100$7cac1218@reston1.va.home.com>
To: <www-rdf-interest@w3.org>
[David Allsopp ]

>
> Patrick.Stickler@nokia.com wrote:
> > [Tom Passin wrote]
> > > Indeed, if you think of a set of triples as being rows in a relational
> > > database table, then ask what would be the primary key of
> > > that table?  The
> > > only sensible answer is that the primary key must be the
> > > combination of the
> > > subject and predicate.  The "semantics" could also be
> > > considered to be a
> > > kind of "business rule", to use an expression from a different domain.
> > > Taking this relational database viewpoint, each node must
> > > necessarily have a
> > > value (or label), but it may be that a particular
> > > implementation could hide
> > > the label, or exclude it from serialization.
> >
> > Exactly. This is what I was trying to get at with my examples that
> > autogenerated identities of "anonymous" nodes based on their
> > "context" made up of the subject and predicate. Having the same
> > consistent identity makes comparison of values and enforcement
> > of constraints much more straight forward.
>
> As I said before; I like the idea, but I don't see how it can work in
> practice, because we don't know the complete context (which may differ
> from agent to agent, and from time to time) and an incomplete context
> can be ambiguous.
>
That's why I said it's hard - I think that's pretty well agreed - but maybe
not hopeless.  Anyway, I'm not ready to give up the hope that this
difficulty can be overcome.

Tom P
Received on Tuesday, 21 August 2001 09:11:31 GMT

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