Re: how does one reconcile delete-using-02.ru to the effect of from/from-named with respect to a constant graph term

On 18/05/15 16:27, james anderson wrote:
> good afternoon;
>
> for the test dawg-delete-using-02a, the query[1] and the ancillary
> dataset documents imply that the constant value in a ‘using' clause
> should override a constant term in a ‘graph' clause.

Hi james,

It would be helpful if you could provide pointers or quotes that lead 
you to the conclusions you state.

The USING , USING NAMED describe a dataset for the WHERE part. They do
not override GRAPH which remains an accessor of named graphs in the dataset.

USING <http://example.org/g3>

so the default graph has the contents of <http://example.org/g3> and 
there are no named graphs.

It does not override the GRAPH use in the pattern - GRAPH still accesses 
a named graph as before.  In this case, the

GRAPH <http://example.org/g2>

isn't going to match - there is no <http://example.org/g2> in the 
dataset - and the DELETE part will make no changes.

Section 3.1.3
"""
The USING and USING NAMED clauses affect the RDF Dataset used while 
evaluating the WHERE clause. This describes a dataset in the same way as 
FROM and FROM NAMED clauses describe RDF Datasets in the SPARQL 1.1 
Query Language.
"""

Section 4.2.3 Dataset
"""
DS is distinguished from GS as they may differ, for instance, due to the 
use of USING [NAMED] to modify DS.
"""


so in the same way

SELECT *
FROM <http://example.org/g3>
WHERE { GRAPH <http://example.org/g2> { ?s ?p ?o } }

has no matches, not does the pattern part of:

DELETE  ...
USING <http://example.org/g3>
WHERE
{
   GRAPH <http://example.org/g2> { :a foaf:knows ?s .
                                   ?s ?p ?o }
}


> the comment in the manifest[2] reiterates this conclusion and a note
> during the approval process indicates the effect of the ‘using’
> clause was a matter of specific deliberation.

> on the other hand, this behavior contradicts the sparql evaluation
> specification[3] among other ways,

[3] does not mention FROM.

> in the interaction between default
> and named graphs, and the update recommendation itself provides only
> the description, that the using is to have the effect of a
> from/from-named
>
> is there some other version or some further explanation for this
> test?
>
> best regards, from berlin, — [1] :
> http://www.w3.org/2009/sparql/docs/tests/data-sparql11/delete/delete-using-02.ru
>
>
[2] : 
http://www.w3.org/2009/sparql/docs/tests/data-sparql11/delete/manifest.ttl
> [3] :
> http://www.w3.org/TR/2013/REC-sparql11-query-20130321/#defn_evalGraph
>

Received on Monday, 18 May 2015 20:24:12 UTC