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Re: RDF query testcases?

From: Libby Miller <Libby.Miller@bristol.ac.uk>
Date: Thu, 16 Jan 2003 17:06:28 +0000 (GMT)
To: Jos De_Roo <jos.deroo@agfa.com>
cc: www-rdf-rules@w3.org
Message-ID: <Pine.GSO.4.44.0301161654060.9686-100000@mail.ilrt.bris.ac.uk>


hi Jos!

So, looking at

http://www.agfa.com/w3c/euler/

and particularly the questions like

http://www.agfa.com/w3c/euler/gedcom-query.n3

you're using n3 to describe an RDF graph and _interpreting_
the graph as a query, is that right? like Pat Hayes said I think - an
RDF graph with a question-mark at the end? So the graph means something
different - a question, rather than a set of statements.

I like this approach very much for testing especially (though I'd use
N-triple rather than N3, there's not a big difference for something
like this I don't think). The only issue I can see is that queries
(although rarely in my experience) could have blank predicates, anbd
predicates can't be bnodes in RDF as far as I know. Do you think this
matters?

For the results, cleverer backends might produce more results in for
the same query, and we'd have to take this into account for describing
the results.

cheers,

Libby



On Thu, 16 Jan 2003, Jos De_Roo wrote:

>
> Hi Libby!
>
> good question; it seems to us that a query is simply
> a set of triples where bnodes play the role of variables
> we then basically can apply a resolution process
>
> [[[
> The resolution process starts with a query. A query is a tripleset.
> The query will be matched against the triplesets of the initial
> graph G and against the rules. The set unifies with a rule when
> one of the triples of the set unifies with the consequent of the
> rule. The set unifies with another set if all triples in the set
> unify with a triple of the other set. This can possibly be done
> in different ways. The result of the unification of two triple
> sets is a list of substitutionlists.
> ]]]
> http://www.agfa.com/w3c/2002/02/thesis/An_inference_engine_for_RDF.html
> and this is work done by Guido Naudts in his master thesis
>
> we also have some running code at http://www.agfa.com/w3c/euler/
> and some testcases starting at http://www.agfa.com/w3c/euler/etc5
>
> but there's still a lot to do...
>
> -- ,
> Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
>
>
>
>                     Libby Miller
>                     <Libby.Miller@bris       To:     www-rdf-rules@w3.org
>                     tol.ac.uk>               cc:     public-esw@w3.org
>                     Sent by:                 Subject:     RDF query testcases?
>                     www-rdf-rules-requ
>                     est@w3.org
>
>
>                     2003-01-16 12:40
>                     AM
>
>
>
>
>
>
>
>
> Hi all
>
> We have some effort in SWAD-Europe [1] to write a document about RDF
> query [see [2]]. Part of this will be FAQ-based - a start is here [3],
> (and I'd be grateful for any FAQs or answers).
>
> The main reason for sending this message it because I've chatted to a
> few people who feel that a collection of RDF query testcases would be a
> useful thing to have, and I can put some effort into this - maybe as a
> minimum, finding out what's already available, and maybe look into some
> ways of enabling one query language implementation to use another's
> testcases.
>
> So, would anyone out there like to share their test and their
> experiences of writing them? I can infer that Jena and 4suite have
> them; I think Mozilla has some too. I've got some here for Inkling:
>
> http://swordfish.rdfweb.org/rdfquery/tests/
> http://swordfish.rdfweb.org/rdfquery/rdf/
> http://swordfish.rdfweb.org/rdfquery/queries/
>
> Basically the test scripts read in
> http://swordfish.rdfweb.org/rdfquery/rdf/query-results-manifest.rdf
>
> which specifies the RDF/XML file to pull in, the query to use and the
> expected number of rows in the resulting table. So it's only a very
> basic test of whether the query engine is functioning.
>
> Any more? Any thoughts?
>
> cheers,
>
> Libby
>
> [1] http://www.w3.org/2001/sw/Europe/
> [2] http://www.w3.org/2001/sw/Europe/plan/workpackages/live/esw-wp-7.html
> [3] http://www.w3.org/2001/sw/Europe/reports/rdf_ql_comparison_report/
>
>
>
>
>
>
>
>
Received on Thursday, 16 January 2003 12:09:50 GMT

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