- From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
- Date: Mon, 26 Sep 2016 14:00:49 -0700
- To: Irene Polikoff <irene@topquadrant.com>, Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de>
- Cc: "public-rdf-sha." <public-rdf-shapes@w3.org>
It's not really a language/wording issue, except perhaps if you are Humpty
Dumpty. There are only two value here, no more. SHACL has always been based
on values, not paths. This is one way in which it differs from shape
expressions.
peter
On 09/26/2016 01:48 PM, Irene Polikoff wrote:
> I thought what Peter is saying that even if the count is four, there are only
> two nodes in the graph in this example, so this is a language/wording issue.
>
> Irene
>
>
> From: Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de
> <mailto:kontokostas@informatik.uni-leipzig.de>>
> Date: Monday, September 26, 2016 at 3:11 PM
> To: "Peter F. Patel-Schneider" <pfpschneider@gmail.com
> <mailto:pfpschneider@gmail.com>>
> Cc: "public-rdf-sha." <public-rdf-shapes@w3.org <mailto:public-rdf-shapes@w3.org>>
> Subject: Re: divergence in the definition of sh:minCount
> Resent-From: <public-rdf-shapes@w3.org <mailto:public-rdf-shapes@w3.org>>
> Resent-Date: Mon, 26 Sep 2016 19:12:00 +0000
>
> Maybe it is something very obvious but I still cannot see it.
>
> however, I improved the wording for the property path value nodes. It was
> using subject and object which was not correct, shapes can use also literals
> as focus nodes
> https://github.com/w3c/data-shapes/commit/f1d525b82ce8a74092826e768159db601270033a
>
> On Mon, Sep 26, 2016 at 6:55 PM, Peter F. Patel-Schneider
> <pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>> wrote:
>
> You mean that you got back 4 results when running the SPARQL query. That's
> different from "the number of value nodes", which is my point.
>
> peter
>
>
> On 09/26/2016 12:30 AM, Dimitris Kontokostas wrote:
> > Hi Peter,
> >
> > I tried your example and I got 4 "value nodes" back which is in line with the
> > duplicate value node comment above.
> >
> > I am trying to see the problem here, is it the following wording from section 4?
> > "For property constraints that have a sh:path the value nodes are the objects
> > in the data graph that can be reached by following the given property path
> > starting with the focus node as subject based on the evaluation rules defined
> > by SPARQL 1.1"
> >
> > I think this can be improved but I cannot see if there is a wrong definition
> > there.
> >
> > Thanks,
> > Dimitris
> >
> > On Sun, Sep 25, 2016 at 12:43 AM, Peter F. Patel-Schneider
> > <pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>
> <mailto:pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>>> wrote:
> >
> > Even if you "count all nodes, even duplicates", there is still a violation in
> >
> > Data:
> > :john :child :bill .
> > :john :son :bill .
> > :john :child :mary .
> > :john :daughter :mary .
> >
> > Shape
> > s:s1 rdf:type sh:Shape ;
> > sh:targetNode :john ;
> > sh:property [ sh:path [ sh:alternativePath ( :child :son :daughter ) ] ;
> > sh:minCount 3 ] .
> >
> > If something other than "A validation result must be produced if the number of
> > value nodes is less than the value of sh:minCount." is desired then this
> > wording can no longer be used, particularly given the wording about path-based
> > property constraints at the beginning of Section 4.
> >
> > peter
> >
> >
> >
> > On 09/24/2016 07:12 AM, Dimitris Kontokostas wrote:
> > > Hi Peter,
> > >
> > > is this about the fact that property paths might return duplicate value nodes
> > > or something else?
> > > In this case, we count all nodes, even duplicates for cardinality restrictions
> > >
> > > Thanks,
> > > Dimitris
> > >
> > > On Fri, Sep 23, 2016 at 9:17 PM, Peter F. Patel-Schneider
> > > <pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>
> <mailto:pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>>
> > <mailto:pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>
> <mailto:pfpschneider@gmail.com <mailto:pfpschneider@gmail.com>>>> wrote:
> > >
> > > The textual and SPARQL definitions of sh:minCount do not align when
> > paths
> > > are allowed.
> > >
> > >
> > > A validation result must be produced if the number of value nodes is
> > less
> > > than the value of sh:minCount.
> > >
> > > SELECT $this
> > > WHERE {OPTIONAL {$this $PATH ?value .}}
> > > GROUP BY $this
> > > HAVING (COUNT(?value) < $minCount)
> > >
> > >
> > >
> > > Peter F. Patel-Schneider
> > > Nuance Communications
> > >
> > >
> > >
> > >
> > > --
> > > Dimitris Kontokostas
> > > Department of Computer Science, University of Leipzig & DBpedia Association
> > > Projects: http://dbpedia.org, http://rdfunit.aksw.org,
> > http://aligned-project.eu
> > > Homepage: http://aksw.org/DimitrisKontokostas <http://aksw.org/DimitrisKontokostas>
> > <http://aksw.org/DimitrisKontokostas <http://aksw.org/DimitrisKontokostas>>
> > > Research Group: AKSW/KILT http://aksw.org/Groups/KILT
> > >
> >
> >
> >
> >
> > --
> > Dimitris Kontokostas
> > Department of Computer Science, University of Leipzig & DBpedia Association
> > Projects: http://dbpedia.org, http://rdfunit.aksw.org, http://aligned-project.eu
> > Homepage: http://aksw.org/DimitrisKontokostas <http://aksw.org/DimitrisKontokostas>
> > Research Group: AKSW/KILT http://aksw.org/Groups/KILT
> >
>
>
>
>
> --
> Dimitris Kontokostas
> Department of Computer Science, University of Leipzig & DBpedia Association
> Projects: http://dbpedia.org, http://rdfunit.aksw.org, http://aligned-project.eu
> Homepage: http://aksw.org/DimitrisKontokostas
> Research Group: AKSW/KILT http://aksw.org/Groups/KILT
>
Received on Monday, 26 September 2016 21:01:24 UTC