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Re: What is an RDF Query?

From: Sandro Hawke <sandro@w3.org>
Date: Mon, 10 Sep 2001 13:57:25 -0400
Message-Id: <200109101757.f8AHvPX32260@wadimousa.hawke.org>
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
cc: www-rdf-rules@w3.org

> > Yep.   This works, but it ends up more complicated than we need, if we
> > just handle existential variables properly.
> 
> I don't understand the need to encode everything in RDF.  Encoding
> everything in RDF ends up with a very complicated system, and most of the
> semantic import will be in the encodings, which are not part of RDF.

The "need" is a perhaps more of an opportunity.  When one is
programming in LISP, one tends to use LISP syntax for almost
everything because one's mental and software machinery is all geared
up for it.

Once we've made it easy to represent and work with knowledge in RDF,
we might as well do it with all our meta-knowledge, control-knowledge,
etc...  

Except for (1) it is sometimes more confusing and (2) it might have big
performance penalties.

DAML+OIL has this same issue, right?  The instance knowledge is in
RDF, which makes perfect sense.  It's a great language for listing the
property/value pairs for objects.  But then the ontology (describing
what kind of properties and values are allowed) is also encoded in
RDF.  What's more, the characterists of the ontology language are
*also* encoded in RDF in http://www.daml.org/2001/03/daml+oil.daml!

So why not describe a query of an RDF dataset in an RDF dataset?

    -- sandro
Received on Monday, 10 September 2001 14:00:03 GMT

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