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Re: OWL tools Re: Tools for 20 million triples?

From: Danny Ayers <danny666@virgilio.it>
Date: Sun, 28 Mar 2004 19:01:32 +0200
Message-ID: <406704EC.8090709@virgilio.it>
To: Dan Brickley <danbri@w3.org>
Cc: Charles McCathieNevile <charles@w3.org>, RDF Interest Group <www-rdf-interest@w3.org>

Dan Brickley wrote:

>* Charles McCathieNevile <charles@w3.org> [2004-03-27 22:20-0500]
>>Hi folks,
>>So it seems there are plenty of systems capable of handling lots of RDF. Are
>>there any that handle OWL (in some version or other) at that scale?
>I guess it depends what you mean by 'handle'.
>OWL descriptions of RDF vocabularies (such as FOAF) license inferences,
>ie. justify you (or your software) concluding new things from a 
>dataset. Tools like Foafbot (http://usefulinc.com/foaf/foafbot) which
>are built on top of generic RDF machinery (in this case Redland) can do
>useful things (justified by OWL) without being complete OWL reasoners.
>For eg. FOAFBot's Web crawler does a bit of 'identity reasoning' based
>on knowing that some but not all FOAF/RDF properties are 
>owl:InverseFunctionalProperty, ie. uniquely identifying. 
>So the good news is that OWL support can be added incrementally. You
>might decide just to support an understanding of inverse properties, 
>eg. making a system understand that foaf:depicts and foaf:depiction say that
>same thing as each other, just expressed inversely.
Which leads in an interesting direction. If IFPs are particularly 
important in your system, you may want to optimise around them without 
worrying about efficiencies elsewhere. There's a Horrocks paper [1] on 
optimising DL subsumption. Perhaps we could do with exploring/compiling 
a list of some comparable (best practices?) possibilities on other 
optimisations - identity resolution, disjoint sets etc.

>The bad news is that I don't have any handy references to systems that
>do this sort of thing...
Nope, me neither.


[1] http://www.dbnet.ece.ntua.gr/~dwq/p19.pdf

Received on Sunday, 28 March 2004 12:01:19 UTC

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