- From: Kingsley Idehen <kidehen@openlinksw.com>
- Date: Wed, 14 May 2008 14:59:29 -0400
- To: Kendall Grant Clark <kendall@clarkparsia.com>
- CC: Michael F Uschold <uschold@gmail.com>, Tim Berners-Lee <timbl@w3.org>, Sören Auer <auer@informatik.uni-leipzig.de>, Chris Bizer <chris@bizer.de>, Frank van Harmelen <frank.van.harmelen@cs.vu.nl>, Semantic Web Interest Group <semantic-web@w3.org>, "Fabian M. Suchanek" <f.m.suchanek@gmail.com>, Tim Berners-Lee <timbl@csail.mit.edu>, jim hendler <hendler@cs.rpi.edu>, Mark Greaves <markg@vulcan.com>, "georgi.kobilarov" <georgi.kobilarov@gmx.de>, Jens Lehmann <lehmann@informatik.uni-leipzig.de>, Richard Cyganiak <richard@cyganiak.de>, Frederick Giasson <fred@fgiasson.com>, Michael Bergman <mike@mkbergman.com>, Conor Shankey <cshankey@reinvent.com>, Kira Oujonkova <koujonkova@reinvent.com>, Aldo Gangemi <aldo.gangemi@istc.cnr.it>, Ivan Mikhailov <iv@openlinksw.com>, Orri Erling <oerling@openlinksw.com>, Alan Ruttenberg <alanruttenberg@gmail.com>
Kendall Grant Clark wrote: > Excerpts from Michael F Uschold's message of Wed May 14 12:06:36 -0400 2008: > >> **JimHendler *summarized things this way: "So what you are really saying is >> scaling is a technology/research challenge now that there's much more out >> there. We need to go beyond just triple stores and get some fast inferencing >> at Web scales. Makes sense to me." >> > > Absolutely. But it's gotten harder lately to find support for that research, > IMO. > > We've been working on this for OWL2 DL-Lite and for EL++, two tractable > profiles of OWL (as Jim well knows! :>). The next version of Pellet [1] will > include an EL-optimized reasoner (though not over secondary storage), and we > just released Owlgres 0.1 [2], which is an OWL2 DL-Lite reasoner for > Postgresql for large data sets. > > >> *MikeUschold *noted that the computational issue of owl:sameAs proliferation >> is a major problem, even if noone is going to load all the semantic web data >> into a single store. For today's triple stores that do limited inference, >> owl:sameAs "has a significant run time" according both to common sense as >> well as the developers of OpenLink's Virtuoso triple >> store<http://docs.openlinksw.com/virtuoso/rdfsparqlrule.html#rdfsparqlruleintro> >> . >> They say it can easily double query >> times<http://www.openlinksw.com/weblog/oerling/?id=1347>. >> > > You don't have to do it at query time. Owlgres does owl:sameAs processing at > load time and so the *query time* cost is negligible. The usual caveats about > tradeoffs and use cases apply, of course. > > Cheers, > Kendall Clark > > 1 http://pellet.owldl.com/ > 2 http://pellet.owldl.com/owlgres > > Kendall, Owlgres is a PostgreSQL application. Why the DBMS specificity? Virtuoso is an Object-Relational DBMS like PostgreSQL and it supports ODBC and JDBC. What does PosgreSQL offer that you may have assumed is/was missing from Virtuoso when developing this application? Note: Some additional context to digest prior to responding: 1. OpenLink Software built the first ODBC Driver for PosgreSQL (at a time when it was Postgre95) 2. We continue to develop and support PostgreSQL ODBC Drivers 3. PostgreSQL was an option during the exploratory days preceding my decision to use Kubl to create Virtuoso [1] 4. Virtuoso is available in Open Source form just like PosgtreSQL I've also added, Orri Erling (Program Manager Virtuoso), Ivan Mikhailov (Lead Developer of Virtuoso's Quad Store functionality realm), and Alan Rutternberg to this thread (Alan is interested in Owlgres and Virtuoso integration). Links: 1. http://virtuoso.openlinksw.com/wiki/main/Main/VOSHistory -- Regards, Kingsley Idehen Weblog: http://www.openlinksw.com/blog/~kidehen President & CEO OpenLink Software Web: http://www.openlinksw.com
Received on Wednesday, 14 May 2008 19:00:20 UTC