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Re: CONSTRUCTing illegal triples should be optional

From: Steve Harris <steve.harris@garlik.com>
Date: Mon, 23 Jul 2012 10:43:48 +0100
Cc: Andy Seaborne <andy.seaborne@epimorphics.com>, SPARQL Working Group <public-rdf-dawg@w3.org>
Message-Id: <7ADBF69E-04B4-49B2-BC66-3E8B91B5B796@garlik.com>
To: Lee Feigenbaum <lee@thefigtrees.net>
+1

On 2012-07-20, at 19:00, Lee Feigenbaum wrote:

> I agree with this.
> 
> Lee
> 
> On 7/20/2012 1:45 PM, Andy Seaborne wrote:
>> -1
>> 
>> SPARQL is defined as CONSTRUCTing RDF graphs.
>> 
>> If an implementation wishes to deviate from that, fine - but it is not compliant.
>> 
>> SPARQL is defined for sending graphs over the wire - that is all.
>> 
>>    Andy
>> 
>> -------- Original Message --------
>> Subject: CONSTRUCTing illegal triples should be optional
>> Resent-Date: Fri, 20 Jul 2012 16:19:26 +0000
>> Resent-From: public-rdf-dawg-comments@w3.org
>> Date: Fri, 20 Jul 2012 12:18:57 -0400
>> From: David Booth <david@dbooth.org>
>> To: public-rdf-dawg-comments <public-rdf-dawg-comments@w3.org>
>> 
>> Regarding this:
>> http://www.w3.org/TR/sparql11-query/#construct
>> [[
>> If any such instantiation produces a triple containing an unbound
>> variable or an illegal RDF construct, such as a literal in subject or
>> predicate position, then that triple is not included in the output RDF
>> graph.
>> ]]
>> 
>> This really bothers me, because: (a) it unnecessarily couples SPARQL to
>> a controversial decision in the RDF WG that may well change in the
>> future, i.e., the prohibition against literals as subjects; and (b) it
>> forces a conforming implementation to perform checks that its user may
>> not want or need.
>> 
>> If a user chooses to generate invalid RDF then that is his/her business.
>> The SPARQL spec should not prohibit it.  If a particular implementation
>> offers the feature of performing this check, then that is fine. But it
>> is unnecessarily draconian to require all implementations to do it.
>> 
>> I suggest changing the above to:
>> [[
>> If any such instantiation produces a triple containing an unbound
>> variable then that triple MUST NOT be included in the output RDF graph.
>> Otherwise, if any such instantiation produces a triple containing any
>> illegal RDF construct, such as a literal in subject or predicate
>> position, then that triple MAY be excluded from the output RDF graph.
>> ]]
>> 
>> 
> 
> 
> 

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Received on Monday, 23 July 2012 09:44:23 GMT

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