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Re: divergence in the definition of sh:minCount

From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
Date: Mon, 26 Sep 2016 08:55:04 -0700
To: Dimitris Kontokostas <kontokostas@informatik.uni-leipzig.de>
Cc: "public-rdf-sha." <public-rdf-shapes@w3.org>
Message-ID: <c89bdfab-c204-90ba-d619-6c6439c026d6@gmail.com>
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>> 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>>> 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>
>     > 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 15:55:38 UTC

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