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RE: RDF query testcase requirements: IRC chat?

From: Seaborne, Andy <Andy_Seaborne@hplb.hpl.hp.com>
Date: Fri, 14 Feb 2003 17:25:44 -0000
Message-ID: <5E13A1874524D411A876006008CD059F061D6522@0-mail-1.hpl.hp.com>
To: "'Libby Miller'" <Libby.Miller@bristol.ac.uk>, "'www-rdf-rules@w3.org'" <www-rdf-rules@w3.org>


> I would suggest sometime in the week of 24th February, maybe Thursday
> 27th at 17:00 GMT.

Great idea - I will try and make it.  

> The main issue for me is how to express the query itself.

Agreed.  I would like to see the expressivity as poer the QL98 paper -
arbitrary graph patterns - including ones that do not serialize
conveniently.

> My inclination is to try and express queries as graphs with parts
> missing, that is, to interpret an RDF graph as a query, as Jos de Roo
> suggested [5].

> I think this would give us one big win, which is that we could ignore
> the syntactic differences between several very similar query languages
> for RDF (although this will by no means encompass all RDF query
> languages). Plus of course, we get the query parser for free.

An alternative would be to express the query as cwm rules of the form:

	{ query pattern } => { output format }

(or some such) then there is a implementation of the query processor as well
:-)

In Jos's message:
> ... 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

OK if blank arcs are allowed (also, with the _:a syntax to relate bNodes to
get arbitrary graph patterns).

	Andy

-----Original Message-----
From: Libby Miller [mailto:Libby.Miller@bristol.ac.uk] 
Sent: 14 February 2003 16:09
To: www-rdf-rules@w3.org
Subject: RDF query testcase requirements: IRC chat?




hi all

As part of the EC SWAD-Europe project [1], I'm writing a report on query
languages for RDF. Rather than repeat lots of excellent work (e.g.
[2][3][4]), I've decided to focus on testcases for RDF query. I started
a thread on query testcases on this list a couple of weeks ago. A
summary is here

http://esw.w3.org/t/view/ESW/RDFQueryTestCases

I've started a wiki page about RDF query testcases requirements:

http://esw.w3.org/t/view/ESW/RDFQueryTestcasesRequirements

I've jotted down some things that I think are required, based on a RDF
query testcases manifest format I've been using for query testcases

http://swordfish.rdfweb.org/rdfquery/tests/query-results-manifest.rdf

and additions to that suggested by Alberto Reggiori. These are just some
rough notes, and before I continue I'd like feedback and input from the
community.

The main issue for me is how to express the query itself.
My inclination is to try and express queries as graphs with parts
missing, that is, to interpret an RDF graph as a query, as Jos de Roo
suggested [5].

I think this would give us one big win, which is that we could ignore
the syntactic differences between several very similar query languages
for RDF (although this will by no means encompass all RDF query
languages). Plus of course, we get the query parser for free.

For a next step with the requirements, we could have a meeting on IRC
to discuss requirements for RDF query testcases, if enough people thought
it was an interesting direction to go in at this stage. Irc meetings
have been interesting and effective for RDF calendar [6].

I would suggest sometime in the week of 24th February, maybe Thursday
27th at 17:00 GMT.

What does everyone think? any takers for a meeting?

cheers

Libby

[1] http://www.w3.org/2001/sw/Europe/
[2] http://139.91.183.30:9090/RDF/publications/tr308.pdf
[3] http://www.w3.org/2001/11/13-RDF-Query-Rules/
[4] http://rdfstore.sourceforge.net/2002/06/24/rdf-query/
[5] http://lists.w3.org/Archives/Public/www-rdf-rules/2003Jan/0004.html
[6] http://www.w3.org/2002/12/cal/
Received on Friday, 14 February 2003 13:07:40 GMT

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