Re: shapes-ISSUE-91 (hsolbrig): Default Cardinality [SHACL Spec]

* Holger Knublauch <holger@topquadrant.com> [2015-09-26 18:59+1000]
> Yes correct. No sh:maxCount triple means it is unlimited. This is
> consistent with how all other constraints work. The datatype of
> sh:maxCount is xsd:integer, so a "*" would not work. sh:maxCount=0
> would mean that no triples are allowed.

Some languages favor readability by defining max as either an unsigned
integer or the token "*".

http://www.w3.org/TR/xmlschema-1/#element-element


> Holger
> 
> 
> On 9/26/15 4:19 PM, Karen Coyle wrote:
> >Holger, are you saying that currently there is no way to specify
> >maxCount = unlimited except to not include maxCount? Presumably
> >either "maxCardinality = *" or "maxCardinality = 0" would convey
> >this.
> >
> >kc
> >
> >On 9/26/15 12:48 AM, Holger Knublauch wrote:
> >>Hypothetically, if we set the default of sh:maxCount to 1. How would one
> >>change it to unlimited?
> >>
> >>Holger
> >>
> >>
> >>
> >>On 9/25/15 10:15 PM, Karen Coyle wrote:
> >>>I think that the cardinality defaults interact with the closed/open
> >>>graph definition. If the graph is open, then a default of
> >>>"minCardinality = 0, maxCardinality = *" is pretty close to
> >>>meaningless. In an open graph, all potential predicates are "optional"
> >>>unless defined otherwise, and specifying optional predicates does not
> >>>invoke any useful behavior. In the case of an closed graph,
> >>>"minCardinality = 0" describes a specific optional predicate.
> >>>
> >>>SHACL, if I understand it correctly, describes an open graph by
> >>>default. This means that only ""minCardinality > 0" can be validated.
> >>>
> >>>Although the statement by Holger that "if something is left
> >>>unspecified then it should count as unconstrained" resonates, I would
> >>>consider the inclusion of a optional property to be specified, not
> >>>unspecified.
> >>>
> >>>kc
> >>>
> >>>On 9/25/15 1:02 AM, Holger Knublauch wrote:
> >>>>I believe if something is left unspecified then it should count as
> >>>>unconstrained. So if no sh:minCount or sh:maxCount is given then it
> >>>>should count as 0..* by default.
> >>>>
> >>>>PROPOSAL: Close ISSUE-91 stating that the default interpretations of
> >>>>sh:minCount and sh:maxCount (and their qualified counterparts) should
> >>>>remain as currently specified.
> >>>>
> >>>>Holger
> >>>>
> >>>>PS: A compact syntax may of course use different conventions and
> >>>>automatically generate the corresponding min/max triples.
> >>>>
> >>>>
> >>>>On 9/25/2015 0:46, RDF Data Shapes Working Group Issue Tracker wrote:
> >>>>>shapes-ISSUE-91 (hsolbrig): Default Cardinality [SHACL Spec]
> >>>>>
> >>>>>http://www.w3.org/2014/data-shapes/track/issues/91
> >>>>>
> >>>>>Raised by: Harold Solbrig
> >>>>>On product: SHACL Spec
> >>>>>
> >>>>>The defaults for cardinality in UML are [1..1]  (see:
> >>>>>MultiplicityElement.lowerBound() and MultiplicityElement.upperBound()
> >>>>>on page 41 of OMG specification ptc/2013-09-05).  Should these be the
> >>>>>defaults for mincount and maxcount in Section 3.1.5 of the SHACL
> >>>>>specification as well?  Currently they are [0..*].
> >>>>>
> >>>>>
> >>>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>
> >>
> >>
> >
> 
> 

-- 
-ericP

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Received on Sunday, 27 September 2015 08:46:05 UTC