Fwd: Re: a concern on SW technologies: document content

---------- Forwarded message ----------
From: Bob DuCharme <bob@snee.com>

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Yes, RDF and related technologies fall short in areas where XML and XQuery
shine, but XML and XQuery fall short in areas where RDF shines. (And they
both fall short in areas where relational databases shine, and... etc.)

RDF is a data model. Certain problem domains map very well to that data
model, especially large collections of assignments of values to objects
that  don't normalize into relational tables well. An add-on like OWL
makes it easier to define relationships between otherwise unrelated
classes of information, making it easier to use the aggregate sources
together.

RDF can add a lot to a publishing system, but tracking the relationship
between in-line elements and their containing block elements (i.e. mixed
content) is not something it can help much. For example, it can be used to
store metadata about documents and document associations as files moves
through a workflow. (So can plain XML as retrieved by XQuery, but
RDF-based data from multiple documents can be aggregated and used with
much less custom coding.)

RDF can be used to track information about any element with its own ID. In
the case of block elements, this is useful for the publishing industry
because if one block of a document stores a recipe, another a book
excerpt, and another a picture, there will be separate metadata to store
about each. Even inline elements as independent units to track can have
value added if they have an ID; a linking element may have a link type
assigned, the date that the link's validity was last verified, etc. Taking
advantage of an inline element's relationship to its containing element,
though, is not something where RDF can help.

Searching within documents is what XQuery is for. Querying information
about the relationships between documents with specific but sometimes
varying semantics is where RDF (/OWL) shines. When searching a collection
of insurance policies from different companies, they will have some fields
in common, some different fields, some fields that look different but mean
the same thing... treating them as a consistent collection will take a lot
of XQuery custom coding, but with RDF + SPARQL, it will only take the
application of an increasingly popular standard way of specifying the
semantics of each company's forms (OWL) to treat the collection as a
single aggregate to query against.

My XML 2006 talk
(http://2006.xmlconference.org/programme/presentations/188.html) was
unfortunately in the same time slot as another one on integration of
different data sources using RDF/OWL
(http://2006.xmlconference.org/programme/presentations/57.html), and this
other one used XQuery as well. I'm looking forward to finding out more
about what Ken and Ronald did and how they did it; more information is
available at http://www.rrecktek.com/xml2006/, although I haven't had a
chance to look closely at it yet.

Bob DuCharme
http://www.snee.com/bobdc.blog


On Sat, December 9, 2006 4:28 am, Danny Ayers wrote:
> Hi Bob,
>
> If you have a minute, I'd be very grateful for your thoughts on the
> post below (from the Semantic Web Education & Outreach list :
> http://lists.w3.org/Archives/Public/public-sweo-ig/2006Dec/0080.html )
>  - let me know if ok to pass back to the list.
>
> Cheers,
> Danny.
>
> ---------- Forwarded message ----------
> From: Lee Feigenbaum <feigenbl@us.ibm.com>
> Date: 08-Dec-2006 21:52
> Subject: a concern on SW technologies: document content
> To: public-sweo-ig@w3.org
>
>
>
> Hi SWEOids,
>
> Wing and I had an interesting and somewhat enlightening conversation with
> another IBMer today. Our colleague was somewhat familiar with the SW world
> and is very familiar with the XML world, and he expressed concerns that SW
> technologies (and RDF / SPARQL in particular) may fall short in one
> prominent area in which XML / XQuery shines: dealing with content-oriented
> (often mixed content) documents. He was concerned about this given some of
> our claims about the value of RDF/SW technologies as a unifying
> environment for data and metadata.
>
> He gave various examples ranging from insurance policies to resumes to
> rentral agreements, with the basic idea being that XQuery can easily
> answer questions that involve searching within a document (or, more-so,
> searching for text in a particular paragraph of a document, perhaps with
> emphasis added) which uses XML markup. He wondered aloud and we discussed
> what the SW approach to this would be, and we agreed that it's lacking
> right now. He expressed worry that whereas XML can wrap data that might be
> best expressed as relational or RDF data (and then join that data in
> XQuery queries with document data), the RDF world may not have as nice a
> story.
>
> I (personally) need to think the issues here through a bit more, but to me
> it was not an objection that I've heard commonly, but it was an
> interesting one to which I had no immediate response, so I wanted to throw
> it out here and solicit thoughts and/or feedback. (I don't think it's
> imperative that we have an immediate or bulletproof response to every
> potential SW objection, but thinking about where the technologies fall
> short in addition to where they excel should help us craft our messaging.)
>
> have a good weekend everyone,
> Lee
>
>
>
>
> --
>
> http://dannyayers.com
>



-- 

http://dannyayers.com

Received on Saturday, 9 December 2006 16:53:55 UTC