Andy, > GRAPH accesses named graphs, not FROM
I thought I'd tried that too, but I've double-checked and it works now. > FROM sets the dataset to be queried - where FROM is allowed, FROM means > load the data from the web and not use the dataset at the service point. Ah, that makes sense now. So, if I read the SPARQL 1.1 Protocol spec properly then default-graph-uri and named-graph-uri parameters of a request are the same as using FROM and FROM NAMED, respectively, in the query itself. Many thanks Philip -----Original Message----- From: Andy Seaborne [mailto:[email protected]] On Behalf Of Andy Seaborne Sent: Wednesday, April 11, 2012 1:12 PM To: [email protected] Subject: Re: [Fuseki] SPARQL 1.1 Protocol and Named Graphs On 11/04/12 12:15, Philip Fennell wrote: > Hello. > > I can quite happily create, retrieve, update and delete Named Graphs in > Fuseki (0.2.1-incubating) using the SPARQL 1.1 Graph Store HTTP Protocol but > when it comes to querying a Named graph over HTTP with the SPARQL 1.1 > Protocol I'm not so lucky it seems... > > I start-up Fuseki with an empty dataset: > >> ./fuseki-server --update --mem /test > > > I create a Named Graph<http://www.books.com/harry-potter> thus: > > PUT > http://localhost:3030/test/data?graph=http%3A%2F%2Fwww.books.com%2Fharry-potter > Content-Type: application/rdf+xml > ... RDF payload ... > > > If I send the following request to query the Named > Graph<http://www.books.com/harry-potter> I get no results: > > GET http://localhost:3030/test/query?query=[URL Encoded SPARQL > Query]&named-graph-uri=http%3A%2F%2Fwww.books.com%2Fharry-potter > > PREFIX dc:<http://purl.org/dc/elements/1.1/> > SELECT * > WHERE > { > $x ?y ?z. > } LIMIT 10 > > I've experimented with using FROM<http://www.books.com/harry-potter> and > FROM NAMED<http://www.books.com/harry-potter> to see what'd happen but one > way or another I cannot get the query to see the Named Graph dataset. > > > Have I missed something fundamentally important? GRAPH accesses named graphs, not FROM SELECT * { GRAPH <http://www.books.com/harry-potter> { $x ?y ?z. } } FROM sets the dataset to be queried - where FROM is allowed, FROM means load the data from the web and not use the dataset at the service point. (In TDB, it selects graphs out of the collection of all graphs - only really useful for FROm and not FROM NAMED). Andy > > > Regards > > Philip > >
