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Re: Updated definitions (constraint)

From: Dan Connolly <connolly@w3.org>
Date: Fri, 17 Jun 2005 09:02:47 -0400
Message-Id: <4c89e138767236e5559b738c537cf90b@w3.org>
Cc: RDF Data Access Working Group <public-rdf-dawg@w3.org>
To: andy.seaborne@hp.com

On Jun 17, 2005, at 8:51 AM, Seaborne, Andy wrote:
> Dan Connolly wrote:
>> On Jun 16, 2005, at 7:44 AM, Dan Connolly wrote:
>>> On Jun 16, 2005, at 7:15 AM, Seaborne, Andy wrote:
>>>
>>>>  In a group, all the group elements have to "pass" a solution for  
>>>> the groiup to match a solution.
>>>
>>> Ah... that's what I was missing. Thanks.
>>>
>>> http://www.w3.org/2001/sw/DataAccess/rq23/#defn_GroupGraphPatter
>> Hmm... what about this case?
>> SELECT ?x WHERE { FILTER ( ?x < 10 ) }.
>> That's got a bzillion solutions, right? Maybe we need a special case  
>> for that?
>> Or maybe it's already syntactically illegal or something?
>
> I think it depends on the evaluation of filter.  As things stand, I  
> read that as an attempt to do "?x < 10" with no bound x hence false.   
> That right, Eric?

Er... what's in Eric's head is not that relevant. Maybe Eric can find  
part of the spec
that explains, but...  My point is that the definition of constraint
doesn't say anything about "bound x"; i.e. the definition does not say  
"take the solutions
you got from other parts of the pattern and check them" as I  
proposed... and even
if it did, the empty pattern has every solution, so it would still need  
something else
to say why this is false.

> 	Andy
>
>
> See also:
> http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2005Jun/ 
> 0034.html
Received on Friday, 17 June 2005 13:02:47 GMT

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