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Re: rdfs:Graph ? comment on http://www.w3.org/TR/rdf11-concepts/#section-dataset and issue 35

From: Jeremy J Carroll <jjc@syapse.com>
Date: Tue, 16 Jul 2013 07:37:35 -0700
Cc: www-archive@w3.org, "Peter F. Patel-Schneider" <pfpschneider@gmail.com>, phayes@ihmc.us
Message-Id: <C1489061-E051-475D-B1F9-9553938BC408@syapse.com>
To: Sandro Hawke <sandro@w3.org>

OK - I am getting started on this 

how about this dataset:


<> a rdf:DirectDataset.
GRAPH _:a { _:a _:a _:a }
GRAPH _:b { _:b _:b _:b }

does _:a = _:b?:


Or this one

<> a rdf:DirectDataset.
GRAPH _:a { <s> <p> <o> }
GRAPH _:b { <s> <p> <o> }
GRAPH _:c { _:a _:a _:a }
GRAPH _:d { _:b _:b _:b }

does _:c = _:d ?

What is the definition of two graphs being equal in this view?

Here is one:
two graphs g and h within a dataset are equal if there exists an automorphism of the dataset mapping each ground node to itself, and inducing a bijection over the set of blank nodes such that the automorphism maps g to h.

(That isn't quite what is intended - since it does not make <A> and <B> equal in this case:

<> a rdf:DirectDataset.
GRAPH <A> { <s> <p> <o> }
GRAPH <B> { <s> <p> <o> }
)

In my view what you call the WebviewDataset is the natural model on the Web, and if this is not to be 'the' way of understanding named graphs because of some other view, I would like that view to be articulated rather than only exemplified.

Jeremy J Carroll
Principal Architect
Syapse, Inc.



On Jul 15, 2013, at 5:39 PM, Sandro Hawke <sandro@w3.org> wrote:

> It follows from this dataset:
> 
> <> a rdf:DirectDataset.
> GRAPH _:a { <s> <p> <o> }
> GRAPH _:b { <s> <p> <o> }
> 
> that _:a = _:b.  
Received on Tuesday, 16 July 2013 14:38:06 UTC

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