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RE: Reification - whats best practice?

From: Alberto Reggiori <alberto@asemantics.com>
Date: Thu, 26 Aug 2004 09:47:43 -0700 (PDT)
To: Patrick.Stickler@nokia.com
cc: chris@bizer.de, www-rdf-interest@w3.org
Message-ID: <20040826094404.U4686@skutsje.san.webweaving.org>

On Thu, 26 Aug 2004 Patrick.Stickler@nokia.com wrote:
>
>
> > >
> > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004JulSep/0328.html
> > >
> >
> > Nice use case. I definitively think DAWG should have
> > something like ?SOURCE
> > in the query language. The semantic *WEB* is about distributed data
> > published by many sources and I don't see the point in having a query
> > langage which can't reflect this.
>
> +1
>

....

> Pat Hayes and Jeremy Carroll can probably provide some
> arguments with more "meat" (there were some MT issues
> which made things hairy), but one reason why bnodes are
> disallowed as graph namess is because bnodes are graph-specific,
> and the intention is that graph names are inter-graph in,
> scope i.e. global. Thus statements about a particular graph
> can occur in some other graph, which would preclude (in
> that case at least) using a bnode.

clear - and perhaps one would want to be able to pin-point to that URI
where to find/ask those triples or WSDL file. And by making those graph
names real URLs or real-resolvable URNs it would make the system even
stronger.

But, in reality bNodes can be very useful in those real-world cases where
the user wants to refer and describe 3rd party data/information, perhaps
owned by somebody else, behind a firewall, having a transient/temporal URL
- or in those cases where a URI can not be invented/generated. And
indirectly refer-by-description to those nodes. Take the "my FOAF profile"
example, where people describe themselves or point to their friends by
his/her foaf:mbox or foaf:mbox_sha1sum - due they do not know or have yet
a URI scheme for people. IMO the same might happen to graphs being RDF
resources as such. With the character/persona FOAF use case above I simply
tried to motivate a bit more all this - and why a single URI might contain
multiple intra/inter-linked graphs. Of course, this does not necessarily
mean that the final system is simpler, even though more general and
flexible :)

> > Historically, TriX allowed bnodes as graph names.

ah, that's interesting - I hope Jeremy or PatH will help me to
understand better about your decision to drop them in the final document.

cheers

Alberto
Received on Thursday, 26 August 2004 16:59:31 UTC

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