Re: Linked Data Aspects of R2RML

Good point Eric!
I did not want to bother you and we can discuss this kind of issue in the
call, but i want to make a point...
it's not semantically correct (or not always) to say that:
http://myrentalstore.com/resource/film/123 owl:samesAs
 http://dbpedia.org/resource/Breakfast_at_Tiffany%27s_%28film%29
because the "owl:sameAs" means that we accept the union between the two
description which is not always the case...
We faced this issue in OKKAM and using the OKKAM system we don't make the
union between different descriptions (provided by the alternative ID uri)
but you simply refer to different descriptions in different data sources.
And OKKAM says that all the descriptions refers to the same thing but NOT
THAT the thing is described by the union of those different descriptions...

Bye
Angela.

<http://dbpedia.org/resource/Breakfast_at_Tiffany%27s_%28film%29>
On Fri, Jan 15, 2010 at 1:47 PM, Eric Prud'hommeaux <eric@w3.org> wrote:

> * Juan Sequeda <juanfederico@gmail.com> [2010-01-14 18:51-0500]
> > Michael and all,
> >
> > I have a question about reusable identifiers.
> >
> > If I have my movie rental company relational database and I want to
> expose
> > it all as Linked Data. What should be the identifier for "Breakfast at
> > Tiffany's?"
> >
> > http://dbpedia.org/resource/Breakfast_at_Tiffany%27s_%28film%29
> > http://data.linkedmdb.org/resource/film/71
> > okkam identifier for Breakfast at Tiffany's (if it exists)
> >
> > or should it be a
> >
> > http://myrentalstore.com/resource/film/123 owl:samesAs
> > http://dbpedia.org/resource/Breakfast_at_Tiffany%27s_%28film%29
>
> While it's fabulous to use URLs for both unambiguity *and*
> exploration, the two are in conflict in most publication scenarios.
> IF you use dbpedia and *everyone* uses dbpedia, data integration
> becomes trivial; people who used to write mashups can now just write
> SPARQL queries.
>
> The downside is that you lose the appealing aspect of controlling what
> content the user sees, which means, you don't get to pepper it with
> links like <rent it> or <if you liked this, you'll also like...>.
>
> The fallback is to have myrentalstore links and some owl:sameAs. The
> user sees what you want them to see, and sparql query authors have a
> small additional burden of including the sameAs in their mashup query.
> (You could have a SPARQL query translator that stuck sameAs in willy
> nilly, but the cost of that query is much higher.)
>
> This problem is apparent in most LOD sites which are actually large
> warehouses. One possible solution is to have a bit more protocol so
> that when you start out using your generic RDF browser on
> myrentalstore, you can follow a link to dbpedia and have the browser
> do an extra query on the myrentalstore SPARQL server to supplement the
> info. Another is to divide data from display:
>  <p><a href="http://myrentalstore.com/resource/film/123">
> http://dbpedia.org/resource/Breakfast_at_Tiffany%27s_%28film%29</a> a <a
> href="http://myrentalstore.com/resource/Classics">
> http://dbpedia.org/resource/Film_Classic</a> .</p>
>
> Most of these solutions have some drawbacks; time will tell what we
> choose and what would should have chosen.
>
> > Audrey Hepburn, can be considered a well known entity with URIs in
> dbpedia,
> > freebase, etc. We know that Audrey Hepburn acted in Breakfast at
> Tiffany's.
> > So should I have my own URI for the movie and reuse an identifier for
> Audrey
> > Hepburn?
> >
> > I agree that we need to offer the possibility in the language to reuse
> the
> > identifiers, I'm just wondering what is the use case.
> >
> >
> >
> > Juan Sequeda, Ph.D Student
> > Dept. of Computer Sciences
> > The University of Texas at Austin
> > www.juansequeda.com
> > www.semanticwebaustin.org
> >
> >
> > On Thu, Jan 14, 2010 at 5:48 AM, Michael Hausenblas <
> > michael.hausenblas@deri.org> wrote:
> >
> > >
> > > All,
> > >
> > > I've put my initial thoughts re the Linked Data aspects of R2RML on our
> > > Wiki
> > > [1]. Please read, review & comment (preferably in the Wiki; saves us
> all
> > > time ;).
> > >
> > > Note that this will be the main discussion point for our upcoming telco
> on
> > > 2010-01-19.
> > >
> > > Cheers,
> > >      Michael
> > >
> > > [1] http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects
> > >
> > > --
> > > Dr. Michael Hausenblas
> > > LiDRC - Linked Data Research Centre
> > > DERI - Digital Enterprise Research Institute
> > > NUIG - National University of Ireland, Galway
> > > Ireland, Europe
> > > Tel. +353 91 495730
> > > http://linkeddata.deri.ie/
> > > http://sw-app.org/about.html
> > >
> > >
> > >
> > >
>
> --
> -ericP
>

Received on Friday, 15 January 2010 15:18:33 UTC