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Re: some GRAPHS strawpolls for today (agenda?)

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Wed, 25 Apr 2012 16:17:24 +0100
Message-ID: <4F981584.2050508@epimorphics.com>
To: public-rdf-wg@w3.org
> 1. The default graph is asserted
>
>    "{<a>  <b>  <c>}" entails turtle("<a>  <b>  <c>")

+1

> 2. Named graphs are not asserted
>
>    "<u>  {<a>  <b>  <c>}" does not entail turtle("<a>  <b>  <c>")

+1

> 3. Named graphs are opaque
>
>    "<u>  {<a>  <b>  <c>}"  does not entail "<u>  {<a>  <b>  _:x}"

-1

Entailment within a graph still applies.

> 4. Graph labels denote just like in RDF
>
>    "{<u1>  owl:sameAs<u2>}<u1>  {<a>  <b>  <c>}"
>    owl-entails
>    "<u2>  {<a>  <b>  <c>}"

    {<u1>  owl:sameAs<u2>}
    <u1>  {<a>  <b>  <c>}
     owl-entails
    <u2>  {<a>  <b>  <c>}

Maybe.  The key is "owl-entails" and any RDF semantics in scope/context.

> 5. Blank nodes labels have file scope

+1

>     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
>
> 6. In trig, @union can be used in place of the default graph
>
>     "@union<u>  {<a>  <b>  <c>}" entails turtle "<a>  <b>  <c>"

In concept, +1

There are some details around here :-)

> 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>}".

+1?

the decision to merge or not merge is an application decision ("do I 
trust <u> graph?" "do I trust source foo?" etc etc) as it is for two graphs.

If app wants to merge to datasets by merging same-label graphs, then 
this is the outcome.

	Andy
Received on Wednesday, 25 April 2012 15:18:01 UTC

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