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
