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Re: RDF+Transformation = XHTML or is there sth like inverse GRDDL?

From: Jacek Kopecky <jacek.kopecky@deri.org>
Date: Wed, 04 Jul 2007 15:50:16 +0200
To: Steve Harris <swh@ecs.soton.ac.uk>
Cc: Danny Ayers <danny.ayers@gmail.com>, al@jku.at, semantic-web@w3.org
Message-Id: <1183557016.4036.156.camel@localhost>

Steve, good idea, that grouping.
Could it be extended for grouping (or arraying) deeper than 1 level? 
Or even recursively? Could get interesting if every part could have
subparts that could have subparts etc.

In that case I guess even CONSTRUCTXML would have to be extended,
something like:

CONSTRUCTXML
<catalogue>
  <product id="{?prodid}">
    {CONSTRUCTXML NAMED part
      <part name="{?partname}">
        {CONSTRUCTXML REF part WITH ?prodid=?partname}
      </part>
     WHERE { ?prodid hasPart ?partName }
    }
  </product>
</catalogue>
WHERE { ?prodid rdf:type Product }

And then it might have to deal with handling loops in the data.

Best regards,
Jacek

On Wed, 2007-07-04 at 14:12 +0100, Steve Harris wrote:
> > But the results table will be:
> >
> >         1  wheel
> >         1  engine
> >         1  chassis
> >         2  antenna
> >         2  receiver
> 
> I've run into this problem a lot as well. I can imagine a SPARQL  
> syntax extension like:
> 
> SELECT DISTINCT ?prodid ?partname
> WHERE { ?prodid rdf:type :Product ;
>                  :hasPart ?partName . }
> GROUP BY ?prodid
> 
> which could return something like:
> ...
> <result>
>    <binding name="prodid"><literal>1</literal></binding>
>    <binding name="partname">
>       <literal>wheel</literal>
>       <literal>engine</literal>
>       <literal>chassis</literal>
>    </binding>
> </result>
> ...
> 
> If you have it in that form it's a lot easier to do the kind of XSLT  
> transforms we're talking about.
> 
> That sort of trick may catch SQL users off-guard, it might be worth  
> writing ARRAY(?partname) or similar. I think it would be pretty handy  
> given the random and surprising cardinality that RDF predicates often  
> have in the wild though.
> 
> - Steve
> 
Received on Wednesday, 4 July 2007 13:50:33 UTC

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