RE: A plea for peace. was: RE: DAML+OIL (March 2001) released: a correction

Peter F. Patel-Schneider wrote:

> [...]
>
> > No one argues the utility of logic, yet logic systems have not achieved
> > widespread usage over the last several decades.
>
> I beg to differ.  One of the great successes of computer science is the
> development and widespread adoption of relational data bases, which are
> logics, or near enough, in my eyes, for the purposes of this debate.

Certainly, and for that matter digital computers in their entirety are based
on binary logic. Relational databases are certainly among the great
successes of computer science. Yet still you would find it difficult to walk
up to any large corporate database, and without documentation, and spending
a fair amount of time, making any real sense of what it contains.

I'd considered it implicit that we were considering systems capable of
making inferences and while perhaps some SQL databases are capable of that,
I don't get that feeling from most of the SQL statements I've seen, nor
their results.

> To further this line of argument, relational data bases had, from the
> beginning, a full-fledged semantics, and, in my opion, would have fallen
> flat on their faces if they did not have same.

Accepting this definition of semantics, a full-fledged semantics does not
itself solve the problem at hand. This problem involves another sense of the
term semantics: in this case understanding what data is in the database, or
perhaps integrating two disparate databases together etc.

I suppose I've always seen as one of the benefits of RDF's triple model the
very fact that it maps so easily onto a relational table -- and admit that I
assumed this abstract syntax would in some sense inherit the formalism of
the underlying database (e.g. this very relational model you mention). If
you say this _isn't_ the case then I certainly agree things need to be
fixed, it just seems as though it shouldn't be that hard to do.

Are you familiar with the XML Query Data Model? Somewhat informally I have
assumed that a benefit of RDF lies in the increased simplicity of not
needing to keep track of element child order, or whether an information item
was an attribute or element. Much of the work of XML Schemas is directed at
mapping arbitrary XML documents to relational databases. RDF has a trivial
mapping which I imagine is a benefit when the model applies to the problem
at hand.

>
> > What interests me about this new experiment is that it will not be self
> > contained and while that will introduce new and perhaps
> difficult problems
> > it will also make things interesting.
>
> Agreed, there are lots of interesting and difficult issues in the
> web.  All
> the more reason to make sure that we are starting with a firm foundation.
>

No argument :-)

-Jonathan

Received on Thursday, 5 April 2001 00:49:44 UTC