RE: RDF in Open Directory project

>      I`m quite newbie in RDF (and whole XML) technology, so I apologize
>   if my question is stupid.

No, your question is very smart.  It's kind of a shame that information on RDF
is organized the way it is: it's not very understandable.  I'm not an RDF expert
myself, but I'll see if I can answer your questions...

>      I`m working on implementing Open Directory (www.dmoz.org) data
>   into my application for performing searches through it. I`ve
>   downloaded dumps in RDF format (at least, they name it so).
>   But as I look at the data it seems that it doesn`t look like
>   canonical RDF, there aren`t <rdf:Description> tags, instead the
>   whole file consists of <Topic> and <ExternalPage> tags.

Topic and ExternalPage are subclasses of RDF:Description (I think.  Could it
possibly be RDF:Bag?).  There is, in addition to the RDF syntax, an RDF schema
which allows you to overload the existing schema of resources, properties and so
on, and define new subclasses based off of the original schema.  This is
horribly confusing to anyone but a machine.

So, somewhere in the RDF, I think you're supposed to assume

<rdfs:Class rdf:ID="Topic">
  <rdfs:comment>The class of topics.</rdfs:comment>
  <rdfs:subClassOf rdf:resource="http://www.w3.org/RDF#Description"/>
</rdfs:Class>

In the Topic below, the description is about a resource which may not exist yet,
but which is known as "Top/News".  It makes a number of statements about this
resource, and tells it has a link to another resource called
http://news.bbc.co.uk.

External page I'm almost certain is a Description because it's using about and
not ID.  It says that this resource has a title and a description, and that's
pretty much that.

I looked around, and I can't figure out where Topic is defined either.  There's
no rdf file which specifies what classes it will use... I suppose you find out
by doing.

Sorry I can't be of more help, but I didn't want you to think people were
ignoring you...

Will.

Received on Friday, 10 November 2000 01:44:40 UTC