- From: Thomas B. Passin <tpassin@comcast.net>
- Date: Wed, 22 Jun 2005 22:41:10 -0400
- To: Chris Purcell <chris.purcell.39@gmail.com>
- CC: Danny Ayers <danny.ayers@gmail.com>, semantic-web@w3.org
Chris Purcell wrote: > >> Moving swiftly on, I think another option would be to use >> reification. Use <code>CONSTRUCT</code> and in it reify the >> statements you want to delete, give them all a property of >> <code>deleteMe</code> or whatever. Might work. > > I've posted something similar ( > http://www.srcf.ucam.org/~cjp39/Peri/KritTer:2005-03-14+WebLog ) > > Add two reification properties, let's call them assertedOn and > deniedOn. Every time a statement is inserted, it gets an assertedOn > property with the current time as the object. To delete a statement, > add a deniedOn statement. To reinsert, add another assertedOn > statement. > > Not only do we get deletion within an open world system, we also get > a history, so one can ask "what was still asserted at time t". Remember two things here - 1) A reified statement is not the same as the corresponding statement made up of those three elements (subject, predicate, object). So asserting something about the reified statement is not - within the standard rdf model - changing anything about the actual triple in the data store. 2) Many, if not most, rdf engines are going to create a bunch of statements that are supposed to be inferred, based on some given triple that is inserted into the data store. How you you going to account for them? Kind of clouds the issue, doesn't it? Tom P -- Thomas B. Passin Explorer's Guide to the Semantic Web (Manning Books) http://www.manning.com/catalog/view.php?book=passin
Received on Thursday, 23 June 2005 02:38:54 UTC