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Re: ACTION-687: editorial edits on update

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Mon, 01 Oct 2012 17:54:34 +0100
Message-ID: <5069CACA.5030804@epimorphics.com>
To: public-rdf-dawg@w3.org


On 25/09/12 22:08, Polleres, Axel wrote:
> In completion of ACTION-687 I reworded the definition in Section
> 4.2.3 as follows:
>
> " [...]Here, skμ(TriplesTemplate) stands for replacing any blank
> nodes occurring in the TriplesTemplate with a new blank node unique
> to the current update request and μ, and different from any blank
> nodes used in DS or in GS. "

I'm not sure this captures it adequately.  See discussion on CONSTRUCT. 
  Any bNode must be a completely new bNode for each template 
substitution, not just the current one (μ).  As the Dataset-UNION may 
not have been done immediately each μ is processed (hence "in DS or in 
GS" does not apply), the text allows the same bNode to be generated for 
two different rows.

Generated blank nodes need to be unique and not used anywhere else. 
(This is not hard to do gloablly)

"""
replacing any blank
nodes occurring in the TriplesTemplate with a new, unique blank node
"""

("fresh" is sometimes used for this)

	Andy

>
> and amended the explaining remarks after the definition linking to
> Andy's additions in section 19.6 of the query doc:
>
> " The function skμ guarantees that blank nodes in the QuadPattern are
> re-instantiated "per solution" μ (analogous to the treatment of blank
> nodes in CONSTRUCT templates in the SPARQL1.1 Query Language) and
> that blank nodes reused within an update request are scoped over the
> entire request, cf. also the respective <a
> href="http://www.w3.org/TR/sparql11-query/#grammarBNodeLabels">
> remarks on scoping of blank nodes within requests in the SPARQL
> grammar</a>. "
>
> best, Axel
>
Received on Monday, 1 October 2012 16:55:03 GMT

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