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Re: some GRAPHS strawpolls for today (agenda?)

From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
Date: Wed, 25 Apr 2012 10:38:30 -0400
Message-ID: <4F980C66.1010602@gmail.com>
To: Sandro Hawke <sandro@w3.org>
CC: public-rdf-wg <public-rdf-wg@w3.org>
This is all predicated on named graphs participating in entailment, which I 
don't really agree with.

On 04/25/2012 10:08 AM, Sandro Hawke wrote:
>
> ====================================
>
>
> 1. The default graph is asserted
>
>    "{<a>  <b>  <c>}" entails turtle("<a>  <b>  <c>")
Absolutely.
> 2. Named graphs are not asserted
>
>    "<u>  {<a>  <b>  <c>}" does not entail turtle("<a>  <b>  <c>")
Definitely.
> 3. Named graphs are opaque
>
>    "<u>  {<a>  <b>  <c>}"  does not entail "<u>  {<a>  <b>  _:x}"
Absolutely NOT!
> 4. Graph labels denote just like in RDF
>
>    "{<u1>  owl:sameAs<u2>}<u1>  {<a>  <b>  <c>}"
>    owl-entails
>    "<u2>  {<a>  <b>  <c>}"

No.
> 5. Blank nodes labels have file scope
>
>     See SPARQL queries in
>     http://www.w3.org/2011/rdf-wg/wiki/Graphs_Design_6.1#Blank_Nodes
>     or Skolemization example in
>     http://lists.w3.org/Archives/Public/public-rdf-wg/2012Apr/0132.html
No, they have graph scope.
>
> 6. In trig, @union can be used in place of the default graph
>
>     "@union<u>  {<a>  <b>  <c>}" entails turtle "<a>  <b>  <c>"
@union seems to be the wrong name for this.
>
> 7. Datasets only say which triples are known to be in a named graph,
>     not which triples are *not* in that named graph.
>
>     The merge of "<u>  {<a>  <b>  <c>}" and "<u>  {<a>  <b>  <d>}" is
>     "<u>  {<a>  <b>  <c>,<d>}".
>
>     Also "<u>  {<a>  <b>  <c>,<d>}" entails "<u>  {<a>  <b>  <c>}".
>
>
Yes
Received on Wednesday, 25 April 2012 14:39:02 UTC

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