W3C home > Mailing lists > Public > public-rdf-wg@w3.org > April 2012

Re: some GRAPHS strawpolls for today (agenda?)

From: Ivan Herman <ivan@w3.org>
Date: Wed, 25 Apr 2012 16:53:33 +0200
Cc: public-rdf-wg <public-rdf-wg@w3.org>
Message-Id: <11151AA3-280A-4634-8CA2-4F5A47897D0E@w3.org>
To: Sandro Hawke <sandro@w3.org>

On Apr 25, 2012, at 16:08 , Sandro Hawke wrote:

> If we're going to talk about graphs today, maybe we can do it in a
> series of decisions.   There's not enough notice to make these binding,
> of course, but maybe we can get a sense of how close we are to
> consensus.
> 
> If we can't even get consensus on a few of these, these I think we
> should stop working on graph semantics in this WG.  I hope we're very
> close to consensus on all of these, except maybe the last, which I could
> see continuing as an open issue well into CR.
> 
> I've erred on the side of brevity here.
> 
>     -- Sandro
> 
> ====================================
> 
> 
> 1. The default graph is asserted
> 
>  "{<a> <b> <c>}" entails turtle("<a> <b> <c>")

Agree

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

Agree

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

Agree

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

Agree


> 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
> 

Not sure. I am not sure I understand the consequences


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

Yes... but I would expect @union to be a directive like @prefix. Is this what you mean?

> 
> 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>}".  
> 

Yes


>   Also "<u> {<a> <b> <c>,<d>}" entails "<u> {<a> <b> <c>}".
> 

Yes

> 
> 


----
Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
FOAF: http://www.ivan-herman.net/foaf.rdf







Received on Wednesday, 25 April 2012 14:51:18 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 22:02:04 UTC