- From: Birte Glimm <birte.glimm@uni-ulm.de>
- Date: Thu, 10 Nov 2011 10:17:49 +0100
- To: Michael Schneider <schneid@fzi.de>
- Cc: public-rdf-dawg-comments@w3.org
Michael, Thank you for your comment and the clarification about the editorial comment regarding infiniteness due to datatype reasoning under OWL's RDF-Based Semantics. The current editor's draft no longer contains the editorial note and includes an even simpler example that already illustrates the point. The current editor's draft is available at: http://www.w3.org/2009/sparql/docs/entailment/xmlspec.xml We would be grateful if you would acknowledge that your comment has been answered by sending a reply to this mailing list. Birte, on behalf of the SPARQL-WG On 30 July 2011 19:36, Michael Schneider <schneid@fzi.de> wrote: > Dear all! > > The SPARQL 1.1 Entailment Regimes LCWD, Section 5.2 "Restriction on > Solutions" in the Chapter defining the OWL 2 RDF-Based Entailment Regime, > contains an example query consisting of several complex class expressions > and an Editorial Note, which states > > It could be the case that this example only applies to the > OWL 2 Direct Semantics and that for the RDF-Based Semantics > one would have to introduce axioms that force a domain > element to exist for each extension of the class expressions > ... > > This is correct. > > There is, however, an alternative kind of query, which would be close in the > spirit of the current query, but without suffering from the problem of the > RDF-Based Semantics that one needs the existence of individuals representing > class or property extensions: > One can use a query based on a /negative data property assertions/, for > example in the following form: > > SELECT ?x WHERE { > _:z rdf:type owl:NegativePropertyAssertion ; > _:z owl:sourceIndividual ex:peter ; > _:z owl:assertionProperty ex:dp ; > _:z owl:targetValue ?x . > } > > The expected possible results of this query would, as for the current query, > be all literals L to which ex:peter does /not/ have a ex:dp-relationship, > e.g. L := "6"^^xsd:integer and so on, so the result set would be infinite, > if not restricted. > > There is a specific RDF-based semantic condition that ensures the existence > of such a "_:z" that combines the triples in the multi-triple representation > of negative property assertions: > > > <http://www.w3.org/TR/2009/REC-owl2-rdf-based-semantics-20091027/#item-semcond-negassert-data-bw> > > Best regards, > Michael > > -- > Dipl.-Inform. Michael Schneider > Research Scientist, Information Process Engineering (IPE) > Tel : +49-721-9654-726 > Fax : +49-721-9654-727 > Email: michael.schneider@fzi.de > WWW : http://www.fzi.de/michael.schneider > ============================================================================== > FZI Forschungszentrum Informatik an der Universität Karlsruhe > Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe > Tel.: +49-721-9654-0, Fax: +49-721-9654-959 > Stiftung des bürgerlichen Rechts > Stiftung Az: 14-0563.1 Regierungspräsidium Karlsruhe > Vorstand: Dipl. Wi.-Ing. Michael Flor, Prof. Dr. rer. nat. Ralf Reussner, > Prof. Dr. rer. nat. Dr. h.c. Wolffried Stucky, Prof. Dr. rer. nat. Rudi > Studer > Vorsitzender des Kuratoriums: Ministerialdirigent Günther Leßnerkraus > ============================================================================== > > -- Jun. Prof. Dr. Birte Glimm Tel.: +49 731 50 24125 Inst. of Artificial Intelligence Secr: +49 731 50 24258 University of Ulm Fax: +49 731 50 24188 D-89069 Ulm birte.glimm@uni-ulm.de Germany
Received on Thursday, 10 November 2011 09:18:32 UTC