Hi Minto On Stanbol I've noticed that some graphs do not appear in TcManager.listTripleColletions. It might have to do something with an invalid URI used as graph named. In your example it seems to that you're nor using correct URIRefs. Could you try if it makes a difference using real uuid-uris?
Cheers, Reto On Mon, May 6, 2013 at 1:29 PM, Minto van der Sluis <[email protected]> wrote: > Hi folks, > > Not sure whether it is my (in)ability to write Sparql queries or > something odd is going on. But I am having some trouble with querying > specific named graphs. > > To give some context before showing the queries. I have a situation > where I have 2 named graphs: > 1) Index named <http://digimelding.nl/AStore/stamIndex> containing > references to other named graphs. > 2) A named graph <7e72ff00-48f1-11e2-bcfd-0800200c9a66> containing > actual data. The graph name is a UUID. > > Querying the first gives expected results. But when querying the second > I do not get the results I expect. > > Query 1: Show all named graphs with actual content(triples). > SELECT distinct ?g > WHERE { > GRAPH ?g { > ?s ?p ?o . > } > } > > Results in: > +------------------------------------------+ > | g | > +------------------------------------------+ > | <7e72ff00-48f1-11e2-bcfd-0800200c9a66> | > | <http://digimelding.nl/AStore/stamIndex> | > +------------------------------------------+ > > Query 2: To show the total number of triples present in both named graphs: > SELECT (COUNT(?s) as ?numberOfTriples) > WHERE { > GRAPH ?g { > ?s ?p ?o . > } > } > > Results in: > +--------------------------------------------------+ > | numberOfTriples | > +--------------------------------------------------+ > | "29"^^<http://www.w3.org/2001/XMLSchema#integer> | > +--------------------------------------------------+ > > Query 3: Get the number of triples present in the index graph. > SELECT (COUNT(?s) as ?numberOfTriples) > WHERE { > GRAPH <http://digimelding.nl/AStore/stamIndex> { > ?s ?p ?o . > } > } > > Results in: > +-------------------------------------------------+ > | numberOfTriples | > +-------------------------------------------------+ > | "1"^^<http://www.w3.org/2001/XMLSchema#integer> | > +-------------------------------------------------+ > > Query 4: In my quest for the getting the results I wanted I played > around with various query forms. In my understanding thuis query should > yield the same results as the previous one. Unfortunately, it doesn't. > SELECT (COUNT(?s) as ?numberOfTriples) > FROM <http://digimelding.nl/AStore/stamIndex> > WHERE { > ?s ?p ?o . > } > > Results in: > +-------------------------------------------------+ > | numberOfTriples | > +-------------------------------------------------+ > | "0"^^<http://www.w3.org/2001/XMLSchema#integer> | > +-------------------------------------------------+ > > Query 5: Every query targeted on a named graph (UUID) with the actual > content gives no results. Clearly this query should return ( total > triples 29 - index triples 1 =) 28 triples. Unfortunately it doesn't. > SELECT (COUNT(?s) as ?numberOfTriples) > WHERE { > GRAPH <7e72ff00-48f1-11e2-bcfd-0800200c9a66> { > ?s ?p ?o . > } > } > > Results in: > +-------------------------------------------------+ > | numberOfTriples | > +-------------------------------------------------+ > | "0"^^<http://www.w3.org/2001/XMLSchema#integer> | > +-------------------------------------------------+ > > My code to execute these queries on Clerezza is actually quite simple: > > Object results = clerezzaManager.executeSparqlQuery( query, new > SimpleMGraph() ); > > In here the query is just a string containing one of the queries as > shown above. Execution uses Clerezza from trunk with my committed > changes to the QueryEngine. > > Does anyone know why query 4 and 5 do not yield the expected outcome? > > Regards, > > misl > > -- > ir. ing. Minto van der Sluis > Software innovator / renovator > >
