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Go ahead with pub

From: Bijan Parsia <bparsia@cs.man.ac.uk>
Date: Mon, 2 Oct 2006 10:14:14 +0100
Message-Id: <D179F871-D1DE-4278-B79E-57C5B5F2364C@cs.man.ac.uk>
To: RDF Data Access Working Group <public-rdf-dawg@w3.org>

Sorry to be late, but there was some confusion about what was going  
on and then I hit the class part of the week.

I think the status part should point to the issues list.

"""Costs: Tableau-based reasoners (at least, the Pellet Demo example  
7) rely on the current, more expressive semantics to match  
implications that are not in a materializable RDF graph."""

No. Pellet uses BNodes as syntax for non-distinguished variables, as  
that's what we were told was the likely syntax for non-distinguished  
variables in SPARQL/DL. The semantics of *all* variables in SPARQL/ 
RDF is semi-distinguished.

I thought the alternative proposal (e.g., from conversation with  
Jeen, Jorge and others) was to *drop* BNodes in triple patterns. That  
does solve all the problems of scope, meaning etc., but it means that  
certain combinations of the axes of distinguishedness will be harder  
to specify (but heck, we can always introduce syntax later).

"""@@ Now we are in CR, shouldn't this be deleted?  Need chair's  
permission.
The working group decided on this design and closed the disjunction  
issue without reaching consensus. The objection was that adding UNION  
would complicate implementation and discourage adoption. If you have  
input to this aspect of the SPARQL that the working group has not yet  
considered, please send a comment to public-rdf-dawg-comments@w3.org."""

I would like that to be deleted because it's confusing on several  
levels (e.g., why doesn't it apply in optional?) I don't particularly  
care that it'd done before pub, but it seems an easy enough move. I  
mean, it doesn't *change* anything!

"""Current conventions for DESCRIBE return an RDF graph without any  
specified constraints. Future SPARQL specifications may further  
constrain the results of DESCRIBE, rendering some currently valid  
DESCRIBE responses invalid. As with any query, a service may refuse  
to serve a DESCRIBE query.""""

I have other comments, both editorial and substantial, but they are  
for post publication, I think.

Cheers,
Bijan.
Received on Monday, 2 October 2006 09:15:05 GMT

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