- From: Bob MacGregor <macgregor@ISI.EDU>
- Date: Thu, 13 May 2004 23:04:23 -0700
- To: Jim Hendler <hendler@cs.umd.edu>, www-rdf-logic@w3.org
- Message-Id: <6.0.3.0.2.20040513225540.01de31b8@tnt.isi.edu>
Jim, I reread what you wrote a couple of more times, still find it a bit confusing, but one phrase that puts me off track is "how OWL extends the relational calculus". Properly speaking, I think you would have to say "how OWL extends a subset of the relational calculus". I'm wondering the following: "Are you giving up some constructs (e.g., compound keys, and the ability to count) while adding others, or are you imagining adding a few more OWL constructs to what is already there (yielding a brand new language strictly more expressive than the relational calculus)? Cheers, Bob At 03:26 PM 5/13/2004, Jim Hendler wrote: >Umm, Bob, I guess I'm confused -- the idea I put forth is to figure out >how OWL extends the relational calculus -- Let's not confuse OWL's >ability to model what is in databases (as you discuss) with OWL's ability >to say things that are not expressible in the database schemas themselves >(as it is quite an expressive language and can say many things way beyond >the relation calculus) -- it's not that I disagree with what you say above >(I don't), it's just that I don't see how it relates to what I was asking... > -JH > > >-- >Professor James Hendler http://www.cs.umd.edu/users/hendler >Director, Semantic Web and Agent Technologies 301-405-2696 >Maryland Information and Network Dynamics Lab. 301-405-6707 (Fax) >Univ of Maryland, College Park, MD 20742 240-277-3388 (Cell) ===================================== Robert MacGregor Senior Project Leader macgregor@isi.edu Phone: 310/448-8423, Fax: 310/822-6592 Mobile: 310/251-8488 USC Information Sciences Institute 4676 Admiralty Way, Marina del Rey, CA 90292 =====================================
Received on Friday, 14 May 2004 02:07:34 UTC