- From: Enrico Franconi <franconi@inf.unibz.it>
- Date: Tue, 20 Sep 2005 01:31:05 +0200
- To: Pat Hayes <phayes@ihmc.us>
- Cc: Ian Horrocks <horrocks@cs.man.ac.uk>, public-rdf-dawg-comments@w3.org, RDF Data Access Working Group <public-rdf-dawg@w3.org>
On 19 Sep 2005, at 23:32, Pat Hayes wrote: >> Though it took some work to get there. I've been testing this account >> with various people who are actively concerned with querying, albeit >> typically against more expressive languages such as OWL. *Serious* >> confusion ensues. > > Hmm, I wonder why. This has seemed kind of obvious since early in the > entire RDF process, surely? BTW, have you tried talking to people who > are familiar with SQL querying? That would be me :-) I argued elsewhere about SQL <http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2005Sep/ 0072.html>. >> While I understand that the charter rules out specification of the >> more expressive bits (though, frankly, I could junk that; I don't see >> that it's a *useful* constraint) > > Ah, there we differ. I see it as central. The primary purpose of > SPARQL is to help get RDF deployed in real applications. Of course, but this does not mean that we can not get also interoperability with OWL-DL like languages, without losing the efficiency of SPARQL for your "syntactic" based queries. > Most of the people working on these applications will not be using > more expressive languages in any depth, and are not interested in > inference or entailment. I find this statement very dangerous to say to a semantic web community. Of course, we want efficient systems, but ideally we also want a semantics behind them. Having no interest in semantics or entailment really means that there should be no interest in *semantics* seriously speaking, so why bother with your long RDF-MT document :-) > If SPARQL gets used for a few years and then a completely different > protocol is developed for 'logical' querying, I will be quite happy: > it will have done its job. If SPARQL is warped or delayed just to > provide it with a logically clean extension path, that warping or > delay is doing far more harm than good, IMO. Our plan is not to delay or to change what has been already done. It is just about giving a nice logic based semantics to what has been done in a way that also opens new possibilities for well founded extensions. So, I agree with your concerns, but if we wark together we can have the cake and eat it too! > For myself, apart from the small group of logic police, whose > objections I can script in advance, *nobody* I have chatted with has > evinced the slightest interest in any formal semantic issues at all. > They tend to regard such matters as arcane academic baloney. So, why did you give us the nice RDF-MT document? This is a very strong statement. I guess we are working with the same spirit. And, by the way, it is not nice to use terms like "logic police"; I'd like to have more politeness in our discussion. >> ). A virtual graph approach, suitably described, might work as well >> for these audience. But the current document is *not* adequate on >> this front. > > I wish to know why, and in what regard, it is inadequate. All the > objections I have read so far have been to the effect that there MUST > be a semantic story which makes querying into a species of > entailment-checking: and this view is, IMO, both wrong and (in the > SPARQL context) wrong-headed. It is false for SQL, probably the most > widely used query language ever. See again above my comments on SQL. cheers --e.
Received on Monday, 19 September 2005 23:31:33 UTC