Re: isolating shapes in named graphs

* Karen Coyle <kcoyle@kcoyle.net> [2014-11-25 16:36-0800]
> 
> 
> On 11/25/14 4:20 PM, Peter F. Patel-Schneider wrote:
> >On 11/25/2014 02:14 PM, Eric Prud'hommeaux wrote:
> >>* Holger Knublauch <holger@topquadrant.com> [2014-11-19 22:36+1000]
> >>
> >>>                                     For the majority of use cases
> >>>you would end up with Shape objects that are mirroring classes,
> >>
> >>I disagree that the majority of shapes would be global invariants.
> >>But regardless, the fact that we don't want to write off the other use
> >>cases implies that we must not require a model which forces one to
> >>retract one schema when looking at another when both should be associated
> >>with particular interfaces.
> >
> >What does "global invariant" mean here?
> 
> 
> Actually, could I ask for a mundane definition of "global
> invariant", since I really don't know what this might mean. Could
> someone put it into everyday language?

Something that is true everywhere rather than only in some context. As
an example, foaf:mbox is an inverse functional property. By using mbox,
you are telling consumers of your data that if they see two things with
the same foaf:mbox, they are the same thing. A cardinality constraint
on foaf:Person will be application-specific, so not an invariant.


> Thanks,
> kc
> 
> >
> >There is no way that constraints can be truly global, i.e., that every
> >use of RDF has to include them all.  I don't see anyone arguing that the
> >mere use of a class requires the use of all constraints associated with
> >that class, which perhaps could be considered to be akin to a global
> >invariant.  All other setups for constraints appear to be situational,
> >i.e., not global.
> >
> >peter
> >
> >
> 
> -- 
> Karen Coyle
> kcoyle@kcoyle.net http://kcoyle.net
> m: 1-510-435-8234
> skype: kcoylenet/+1-510-984-3600
> 

-- 
-ericP

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Received on Wednesday, 26 November 2014 06:11:37 UTC