Re: Decentralized RDF Distribution

Inserts may have been solved as far as the simple mechanics of
publishing them is concerned, but the semantic aspects are essentially
the same as those of updates and deletes:  you have to deal with
temporal (or nonmonotonic) effects:  specifically, the idea that the set
of assertions has now changed, and that may change what you now conclude
from the set of assertions (a subsequent email has pointed out that an
update can be considered a combined delete-and-add operation).  The
whole issue of transactions (in the database sense) comes in too, since
you may want to make what is a semantically-consistent modification to
the "database" that consists of several distinct operations (inserts,
deletes, modifys), and want somehow to bracket that set of operations.

--Frank

Aaron Swartz wrote:
> 
snip
> 
> ***Inserts
> 
> Inserts (adding triples) has been already solved. To insert data to
> the decentralized database, you simply publish it to the Web at a
> well-known location.
> 
> ***Updates and Deletes
> 
> Updates (modifying triples) and deletes (removing triples) are more
> difficult, and require entering an area that RDF has been afraid to
> touch: time. Most RDF systems do not factor time into the equation, or
> at least, they do it in a simplistic way.
> 

-- 
Frank Manola                   The MITRE Corporation
202 Burlington Road, MS A345   Bedford, MA 01730-1420
mailto:fmanola@mitre.org       voice: 781-271-8147   FAX: 781-271-8752

Received on Monday, 19 February 2001 11:21:45 UTC