Re: RDF/XML Syntax Specification (Revised) W3C Working Draft published

From: Mike Moran <mmoran@netphysic.com>
Subject: Re: RDF/XML Syntax Specification (Revised) W3C Working Draft   published
Date: Thu, 20 Dec 2001 16:16:29 +0000

> Brian McBride wrote:
> 
> > At 14:00 19/12/2001 +0000, Dave Beckett wrote:
> > 
> >>   <rdf:Description rdf:about="http://example.org/common">
> >>     ... shared properties here
> >>   </rdf:Description>
> >>
> >>   <rdf:Description rdf:about="http://example.org/tom">
> >>     <rdf:type rdf:resource="http://example.org/common"/>
> >>     .. more properties here ...
> >>   </rdf:Description>
> >>
> >>   <rdf:Description rdf:about="http://example/jane">
> >>     <rdf:type rdf:resource="http://example.org/common"/>
> >>     .. more properties here ...
> >>   </rdf:Description>
> > 
> > 
> > Might want to be a little careful here.  Given this graph, many 
> > implemenations if asked:
> > 
> >   what is the value of the sharedProperty of tom
> > 
> > will not give an answer given this modelling style.
> 
> 
> What do you mean by "won't give an answer"? Does this mean it will fail 
> in some way, or will it just give a dumb "I don't know"?
> 
> I appreciate the help on the modelling front, but I really can't use 
> this if it is not portable.
> 
> 
> --
> Mike

Well let's put it this way.

<rdf:Description rdf:about="http://example.org/common">
   <age>10</age>
</rdf:Description>

<rdf:Description rdf:about="http://example.org/tom">
    <rdf:type rdf:resource="http://example.org/common"/>
    <shoesize>7</shoesize>
</rdf:Description>

<rdf:Description rdf:about="http://example/jane">
    <rdf:type rdf:resource="http://example.org/common"/>
    <shoesize>8</shoesize>
</rdf:Description>

does *NOT* imply that Tom's age is 10, nor does it imply that Tom has an
age.  No ifs, ands, or buts!

Any RDF implemenation that behaves otherwise is broken!

Peter F. Patel-Schneider
Bell Labs Research

Received on Thursday, 20 December 2001 12:12:48 UTC