Andy--
Is that warning something I need to fix in TIM, or is it coming from the query
machinery (and therefore something that is probably beyond me for the moment)?
---
A. Soroka
The University of Virginia Library
> On Jul 7, 2016, at 8:32 AM, Andy Seaborne <a...@apache.org> wrote:
>
> Hi,
>
> > DatasetFactory.create();
>
> Union graph doesn't yet work on general datasets consistently.
>
> It works for TDB and for TxnMem (also known as TIM) - in the latter case the
> warning from the OpExecutor comes out but it's wrong.
>
> Andy
>
> On 05/07/16 17:15, François-Paul Servant wrote:
>> Hi,
>>
>> I'm trying to query the named graphs of a TDB dataset using
>> <urn:x-arq:UnionGraph>, but I must be missing something. Is there something
>> special to do in order to use <urn:x-arq:UnionGraph> as a graph name in a
>> query?
>>
>> Here is what I'm trying (this test uses a memory dataset: only works with
>> 3.1.1-SNAPSHOT. Normally, I use TDB)
>>
>> TIA,
>>
>> fps
>>
>> package sometests;
>>
>> import static org.junit.Assert.*;
>>
>> import org.apache.jena.query.Dataset;
>> import org.apache.jena.query.DatasetFactory;
>> import org.apache.jena.query.Query;
>> import org.apache.jena.query.QueryExecution;
>> import org.apache.jena.query.QueryExecutionFactory;
>> import org.apache.jena.query.QueryFactory;
>> import org.apache.jena.query.QuerySolution;
>> import org.apache.jena.query.ResultSet;
>> import org.apache.jena.rdf.model.Model;
>> import org.apache.jena.rdf.model.ModelFactory;
>> import org.junit.Test;
>>
>> public class UnionGraphTest {
>>
>> @Test public final void test() {
>> Model m = ModelFactory.createDefaultModel();
>> m.add(
>> m.createResource("http://ex.com/s";),
>> m.createProperty("http://ex.com/p";),
>> m.createResource("http://ex.com/o";));
>> Dataset ds = DatasetFactory.create();
>> ds.addNamedModel("http://ex.com/g";, m);
>>
>> // query using the named graph: return some results
>> doIt(ds, "http://ex.com/g";);
>> // same query, using urn:x-arq:UnionGraph, doens't return any result
>> doIt(ds, "urn:x-arq:UnionGraph");
>> }
>>
>> private void doIt(Dataset ds, String graphName) {
>> String queryString = "SELECT * WHERE { GRAPH <" + graphName + "> {?s ?p
>> ?o} }";
>> Query q = QueryFactory.create(queryString) ;
>> QueryExecution qexec = QueryExecutionFactory.create(q, ds);
>> ResultSet rs = qexec.execSelect();
>> assertTrue(rs.hasNext());
>> for (;rs.hasNext();) {
>> QuerySolution sol = rs.next();
>> System.out.println(sol);
>> }
>> }
>> }
>>
>
