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Context Tags, Context Sets and Beyond Named Graphs...

From: Paul Houle <ontology2@gmail.com>
Date: Mon, 18 Jan 2010 13:27:55 -0500
Message-ID: <3e12f6f41001181027v747801a8seda19541e438c0a4@mail.gmail.com>
To: public-lod@w3.org
For a while I've been struggling with a number of practical problems working
in RDF.  Some of these addressed by Named Graphs as they currently exists,
but others aren't.

Over the weekend I had an idea for something that I think is highly
expressive but also can be implemented efficiently.

The idea is that the context of triple can be,  not a name,  but a
collection of tags that work like tags on delicious,  flickr,  etc.  Tags
are going to be namespaced like RDF properties,  of course,  but they could
have meanings like:


Individually I call these "Context Tags",  and the set of them that is
associated with a triple is a "Context Set".

Now,  named graphs can be composed from boolean combination of tags,  such





Note that this is a feature of the underlying storage layer that can be
exploited by layers of the RDF store that are above:  for instance,
 something just above the storage layer could hash the subject URL and then
pass a physical partition tag to that the actual storage layer.  Similarly,
 security rules could be applied automatically.


There are many details to be filled in and features that could be added.
 For instance,  I could image that it might be useful to allow multiple
"context sets" to be attached to a triple,  for instance,  if you had the

:WarpDrive :isA :SpacePropulsionDevice

it might be desirable to assert this as

#RealWorld #NotTrue

and to also assert that it is


I've thought through the implications of this less,  however.

The immediate use for this system that I see is that existing query
mechanisms for named graphs can be applied to the computed graphs.
 Inference mechanisms that can do other things with "context tags" is a wide
open question.


Anyhow,  I want this pretty bad.  (i) If you're selling this,  I'm buying;
 (ii) if you want to build this,  contact me.
Received on Monday, 18 January 2010 18:28:27 UTC

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