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Re: RDF query testcase requirements: IRC chat?

From: Alberto Reggiori <areggiori@webweaving.org>
Date: Mon, 17 Feb 2003 16:35:46 +0100
Cc: www-rdf-rules@w3.org, Alberto Reggiori <areggiori@webweaving.org>
To: Libby Miller <Libby.Miller@bristol.ac.uk>
Message-Id: <7BA35F22-428D-11D7-8864-000393A63C18@webweaving.org>

On Friday, February 14, 2003, at 05:09  PM, Libby Miller wrote:

> 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 can not access the above pages at the moment but I look into those 
later on...

> 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

it looks good - I like a lot the use of N-Triples/N3 as input syntax 
with bNodes for the query but I wondering how we could express in 
N-Triples/N3 additional constraints such the ones with AND clause in 
Squish/RDQL e.g. SELECT ?x, ?y WHERE ...... AND (?x < 20 && ?y eq 
'blaa' || ?y =~ /laa/ ) or one of your SquishQL examples [1] (such 
additional constraints clauses are not in the original QL98 paper). 
Anyway, even if I feel that developers and coders are still liking much 
more the SQL-ness of RDF query languages, the use of N-Triples/N3 as a 
good "neutral" syntax to express simple sub-graph matching and 
transformations in queries it could be a win win point.

For the result set [2] in your manifest file you used some vocabulary 
which reminds to me about XHTML TABLEs - I just had a try to markup 
your sample result set as XHTML like RDF document (see 
attachment)...nothing more than an interesting experiment :-)

> 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].


but we need to decide what to do with meaty constraints/features such 
as AND clauses in SquishQL/RDQL or similar in other query languages.

> 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.

Perhaps we could split up the test cases more:

- sub-graph matching/selection and transformation tests (N3/N-Triples)
- query language specific constraints and rules tests (native query 

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

It sounds good to me as well - I should be able to make it even if I 
will be traveling from the 22-28. Some hotel room with a telephone line 
should be enough to make it :-)


[1] http://swordfish.rdfweb.org/rdfquery/tests/queries/q5b.sq
[2] http://swordfish.rdfweb.org/rdfquery/tests/rdf/rs/q3.rdf

Received on Monday, 17 February 2003 10:33:44 UTC

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