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From Andy Seaborne <a...@apache.org>
Subject Re: FROM clause ignored by QueryExceutionFactory
Date Tue, 03 Dec 2013 12:42:39 GMT
On 03/12/13 12:27, Reto Bachmann-Gmür wrote:
> Hello
>
> Encountered an issue in clerezza of which the root cause seems to be in
> Jena so forearding this here. The code is using jena-core and -arq version
> 2.11.

Work for me (using TDB which, from the way the question is asked is what 
you are doing else the thing is meaning less as it will deref 
<urn:x-foo:bar>).

-------------- D.trig
prefix : <http://example/>

:s :p :o .

:g1 { :s1 :p1 :o1 }
:g2 { :s2 :p2 :o2 }
--------------
tdbloader --loc=DB D.trig
--------------
SELECT *
FROM <http://example/g1>
WHERE {
    ?s ?p ?o
}
--------------
-------------------------------------------------------------------
| s                   | p                   | o                   |
===================================================================
| <http://example/s1> | <http://example/p1> | <http://example/o1> |
-------------------------------------------------------------------

>
> qexec = QueryExecutionFactory.create("SELECT  *
> FROM <urn:x-foo:bar>
> WHERE { ?s ?p ?o }", dataset);

what kind of dataset is 'dataset'?  Is it wrapping anything?

> qexec.execSelect();
>
> It seems to me that for this query the default graph in the dataset should
> be ignored and instead a graph <urn:x-foo:bar> be looked up.

Yep.

> However it
> seems that only the default graph which is accessed via
> dataset.asDatasetGraph().getDefaultGraph() is used.

dataset.asDatasetGraph().getDefaultGraph()

will still be the storage default graph.

> Is there some special setting to have the FROM clause used?

No.

	Andy

>
> Cheers,
> Reto
>
>
> ---------- Forwarded message ----------
> From: Reto Bachmann-Gmür <reto@apache.org>
> Date: Tue, Dec 3, 2013 at 1:05 PM
> Subject: Jena based SPARQL QueryEngine: FROM claused ignored
> To: dev@clerezza.apache.org
>
>
> Hello,
>
> I've been investigating the issue that the FROM-clause is ignored and I've
> opened CLEREZZA-846.
>
> The query is passed including its from clause to
> QueryExecutionFactory.create(Query, dataset), however only the default
> graph is accessed in the underlying dataset.
>
> So the FROM in
>
> SELECT  *
> FROM <urn:x-localinstance:/graph-access.graph>
> WHERE { ?s ?p ?o }
>
> seems to be just ignored. Any ideas?
>
> Cheers,
> Reto
>


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