- From: Michael Schneider <schneid@fzi.de>
- Date: Fri, 18 Nov 2011 19:22:53 +0100
- To: <public-rdf-dawg-comments@w3.org>
- CC: <birte.glimm@uni-ulm.de>
Dear SPARQL Working Group, as far as I can see, the new example works well and is indeed simpler than the one that I have proposed. I acknowledge that my comment has been answered. Best regards, Michael Am 20:59, schrieb Birte Glimm: > 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 ==============================================================================
Received on Friday, 18 November 2011 18:23:34 UTC