Hi Andy, > So far - one off list, two on-list and one [email protected] emails > about this, all in less than 4 hours. :-)
Sorry about the extra noise. Looks like Arthur and I were independently pursuing the same issue. > Would you like to propose a patch? (it'll get done quicker > that way) > > See > ... pfunction/function/container.java I'll be on vacation for a few days, starting tomorrow, but I'll try to play around with it when I get back. Thanks, Frank. Andy Seaborne <[email protected]> wrote on 06/15/2011 12:45:01 PM: > [image removed] > > Re: Possible ARQ bug? > > Andy Seaborne > > to: > > jena-users > > 06/15/2011 12:45 PM > > Please respond to jena-users > > So far - one off list, two on-list and one [email protected] emails > about this, all in less than 4 hours. :-) > > On 15/06/11 16:53, Frank Budinsky wrote: > > > > > > Hi, > > > > I'm having a problem querying for rdfs:member predicates. Here is a test > > program: > > > > public static void main( String[] args ) > > { > > Dataset dataset = TDBFactory.createDataset(); > > Model model = dataset.getDefaultModel(); > > //PropertyFunctionRegistry.get().remove(RDFS.member.getURI()) ; > > String xml = > > "<?xml version=\"1.0\"?>" + > > "<rdf:RDF xmlns:rdf= > > \"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"; " + > > " xmlns:rdfs= > > \"http://www.w3.org/2000/01/rdf-schema#\";>" + > > "<rdf:Description rdf:about= > > \"http://example.com/query\";>" + > > "<rdfs:member rdf:resource= > > \"http://example.com/bugs/5\"; />" + > > "<rdfs:member rdf:resource= > > \"http://example.com/bugs/4\"; />" + > > "<rdfs:member rdf:resource= > > \"http://example.com/bugs/3\"; />" + > > "<rdfs:member rdf:resource= > > \"http://example.com/bugs/2\"; />" + > > "<rdfs:member rdf:resource= > > \"http://example.com/bugs/1\"; />" + > > "</rdf:Description>" + > > Out of curiousity, why not use a container? > > (OK - they aren't nice but then none of the datastructures are nice) > > > "</rdf:RDF>"; > > model.read(new ByteArrayInputStream(xml.getBytes()), null); > > String queryString = > > "PREFIX rdf: > > <http://www.w3.org/1999/02/22-rdf-syntax-ns#> " + > > "PREFIX rdfs:<http://www.w3.org/2000/01/rdf-schema#> " + > > "SELECT ?resource ?member WHERE { " + > > " ?resource rdfs:member ?member " + > > " } "; > > > > Query query = QueryFactory.create(queryString); > > QueryExecution qexec = QueryExecutionFactory.create(query, > > dataset); > > ResultSet result = qexec.execSelect(); > > ResultSetFormatter.out(System.out, result, query); > > qexec.close(); > > } > > > > When I run it, I'm getting no results. > > > > If I uncomment this line: > > > > //PropertyFunctionRegistry.get().remove(RDFS.member.getURI()) ; > > > > then it returns the 5 expected results. > > > > It seems that when rdfs:member inferencing is enabled, it no longer matches > > concrete rdfs:member predicates. Is that not an ARQ bug? > > There's no reason I can think of why it shouldn't also look for > rdfs:member. Would you like to propose a patch? (it'll get done quicker > that way) > > See > ... pfunction/function/container.java > > (there is a small issue about cardinality of mixed use over rules but > this does not really makes it worse or better) > > An idiomatic trick is: > > { ?s ?p ?o . FILTER(?p = rdfs:member) } > > and it scales, oddly, because identify optimization happens after > property function spotting. > > Andy > > > > > Thanks, > > Frank
