W3C home > Mailing lists > Public > public-owl-wg@w3.org > June 2008

Re: One comment on RDF mapping [related to ISSUE 67 and ISSUE 81]

From: Alan Wu <alan.wu@oracle.com>
Date: Fri, 13 Jun 2008 10:07:25 -0400
Message-ID: <48527F1D.1030108@oracle.com>
To: Bijan Parsia <bparsia@cs.man.ac.uk>
CC: OWL Working Group WG <public-owl-wg@w3.org>

Bijan,
>
>> Bijan,
>>
>> Sorry for the delayed response.
>>
>> Seems that we don't quite agree on the how much additional cost by 
>> leaving axiom triples out.
>> I am glad to see at least we agree that it requires a more 
>> sophisticated  implementation. :) Can I  ask the WG then to simply 
>> the mapping so that unsophisticated developers like me
>> have an easier time implementing OWL2 in a commercial product. I 
>> believe that is a very reasonable
>> request.
>
> It needs to be balanced by other considerations. 
That is fair. BTW, I forgot to mention that adding the axiom triple 
won't cause a huge expansion of the ontology. Do we
truly worry about, say 20%, size increase?
> As I've pointed out, it's not clear at all to me that in the situation 
> you've outlined (lots of annotated triples in a large kb) that you can 
> *avoid* the need for a sophisticated implementation. If people are 
> querying for annotations, you have to do something to cope with 
> mapping the reified triples to the non-reified one. Better to do that 
> at load time.
Well, it really depends. If an implementation chooses to optimize the 
performance for query/inference over non-reifiied data and
put a much lower priority on query over reified data, then such a 
sophisticated implementation may not be necessary.

> Plus, there's a clear bit of advice for people to optimize loading: 
> Don't randomize your triples.
>
That is a good advice for tools that generate N-Triples :)

Cheers,

Zhe
Received on Friday, 13 June 2008 14:09:20 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 13 June 2008 14:09:21 GMT