Re: SPARQL and the owl web language

From: Matt Williams <matthew.williams@cancer.org.uk>
Subject: Re: SPARQL and the owl web language
Date: Sat, 18 Mar 2006 13:58:52 +0000

> Dear Claudio,
> 
> No, sensible questions, I think.
> 
> AFAIK (corrections welcome) SPARQL will not return OWL (or RDFS) 
> inferences. However, if you run a reasoner (e.g. Pellet, KOAN2, Racer, 
> FACT ++) over the rdf graph, then it will make new inferences, and then 
> you could query the inferred graph.

Well, this is quite problematic.  The set of OWL inferences over an RDF graph
is infinite, so directly querying is out.  Even if you think of the graph as
only virtually being there, there are many other problems, some of which have
been discussed in the DAWG.

> However, happily, Pellet contains a SPARQL query function that takes 
> SPARQL queries and does the inferencing bit for you.

I'm not sure how Pellet sidesteps the problems using SPARQL and OWL.  I'll let
the Pellet team speak for themselves.

[...]

> My suggestion would be Pellet.
> 
> HTH,
> Matt

Peter F. Patel-Schneider
Bell Labs Research

Received on Saturday, 18 March 2006 21:15:43 UTC