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Re: new version of fed query

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Mon, 20 Dec 2010 16:10:22 +0000
Message-ID: <4D0F7FEE.8000207@epimorphics.com>
To: Carlos Buil Aranda <cbuil@fi.upm.es>
CC: SPARQL Working Group <public-rdf-dawg@w3.org>
Hi Carlos,

A few comments on the new version of Basic Fed Query.

Sec 3: I didn't see what this adds as the examples earlier have the 
syntax and the formal defn is in the grammar itself.  Se also commnets 
on the length of the doc.

Service silent: I'm not sure it's a good idea to silently fail in the 
case of a bad SERVICE request because it then looks like there were no 
results.  I suggest instead that we define SERVICE for the case where it 
works, and state that if there is an error then something implementation 
specific happens.  Only a 404 from a "SERVICE ?service" seems to me to 
be the same as no results.  The case of endpoint currently down or 
inaccessible seem rather different.

Sec 4.2 example of bindings translated to UNION.  The bindings table is 
joined to the rest of the pattern - do you have a proof it's equivalent 
to the substitute/union translation in all cases?

MIME Type: I'd like this to be application/sparql-query with extension 
.rq, not sparql-query-fed and extension .frq. (it says .rq the first tme 
and .frq the second time) I don't see it's any different to a SPARQL 
query.  It's useful to register ".rq".

Doc length: While we have said that we'd incorporate this into the main 
query document, I'm now owdoenrign if this is a good idea.  The content 
of the doc is 9 pages of content.   That's a lot to put in rq25 and big 
enough to be it's own document.  Suggestion: keep it in the main 
grammar, have a reference from the query document to federated query in 
the intro and note in the grammar section it includes the grammar rules 

(To be a bit contrary to the above point):
BINDINGS: Should we separate this from SERVICE because it's used in the 
(non-SERVICE) query sent to the remote endpoint.


On 20/12/10 09:18, Carlos Buil Aranda wrote:
> here is the URL, just in case:
> http://www.w3.org/2009/sparql/docs/fed/service
> Carlos
> On 20/12/2010 9:02, Carlos Buil Aranda wrote:
>> Dear all,
>> I have upload a new version of the Basic Fed query. Please, any
>> comment is very welcomed. What I did mainly is to add examples (as in
>> the query 1.1 document), add a simple syntax section, add more simple
>> way of defining semantics (algebraic version, maintaining the previous
>> one), following all the same structure. In the semantics section I did
>> not know exactly what to maintain, so suggestions are very welcomed.
>> cheers,
>> Carlos
Received on Monday, 20 December 2010 16:11:04 UTC

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