Hi Paolo,
Have you tried the Example9 program which demonstrates the use of ASK queries
in the Jena Provider documentation at:
http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtJenaProvider
Also, please confirm the version of the Virtuoso server, Jena Provider , Jena
Framework and JDBC Driver being used:
virtuoso-t -?
java -jar virt_jena.jar
java -jar virtjdbc3.jar
Best Regards
Hugh Williams
Professional Services
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On 29 Jan 2014, at 20:07, Paolo Ciccarese <paolo.ciccar...@gmail.com> wrote:
> I am trying to check for the existence of a graph and if I execute this query
> in the Conductor
> ASK { GRAPH <http://example.org/tests/graph/001> { ?s ?p ?o . } }
> returns 'false' when the graph is not there.
>
> However, if I run the same query with Jena and the Virtuoso Jena Provider I
> always get back 'true':
>
> VirtGraph set = new VirtGraph ("jdbc:virtuoso://localhost:1111", "dba",
> "dba");
> String query = "ASK { GRAPH <http://example.org/tests/graph/001> { ?s ?p ?o .
> } }";
> Query sparql = QueryFactory.create(query);
> VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (sparql,
> set);
> boolean result = vqe.execAsk();
>
> Any advice that can help me out?
>
> Thank you in advance,
> Paolo
>
>
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security issues and trends. Skip the complicated setup - simply import
a virtual appliance and go from zero to informed in seconds.
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