CODEWITHSUNDEEP
virtuoso
Fopa Léon Constantin
Fopa Léon Constantin

Reputation: 12363

virtuoso-opensource: trouble while (jena) querying data loaded using vload script?

I followed this article on "Installing and Managing Virtuoso SPARQL Endpoint" (http://logd.tw.rpi.edu/tutorial/installing_using_virtuoso_sparql_endpoint)

After loading data from a ntriple file with the following command

sudo ./vload nt /path/to/data/file/data.nt http://www.soctrace.org/ontologies/st.owl

I successfuly queried those data from the Web interface SPARQL endpoint located at http://localhost:8890/sparql

SELECT ?s ?p ?o WHERE { ?s ?p ?o }

However, I'm interested on querying those data from jena, so I ran the following Java code 

public void queryVirtuoso( ) {

    Model model = VirtModel.openDatabaseModel("http://www.soctrace.org/ontologies/st.owl", "jdbc:virtuoso://localhost:1111", "dba", "dba");        

    // Query string.
    String queryString = "SELECT ?s ?p ?o WHERE {?s ?p ?o}" ; 
    System.out.println("Execute query=\n"+queryString) ;
    System.out.println() ;


    QueryExecution qexec = VirtuosoQueryExecutionFactory.create(queryString, model) ;
    try {
        ResultSet rs = qexec.execSelect() ;
        System.out.println("Number of results founded " + rs.getRowNumber());           
    } finally {
        qexec.close() ;
    }

}

But unfortunatly the code returns no result.

It seems that the first parameter of the openDatabaseModel from my code is not correct but I don't know what the correct value is.

Does someone have any indication about how to query a virtuodo graph from Jena giving that data are imported using vload script ?

Best regards,

Upvotes: 0

Views: 72

Answers (1)

chile
chile

Reputation: 734

If you not sure about the graph-name, you might look them up in the LinkedData tab in you Virtuoso conductor. It should also be possible to use VirtModel.openDatabaseModel without a graph name (connectionURL, username, password)...

Upvotes: 1

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