- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Thu, 25 Mar 2004 19:30:52 -0500
- To: Dan Connolly <connolly@w3.org>
- Cc: Rob Shearer <Rob.Shearer@networkinference.com>, RDF Data Access Working Group <public-rdf-dawg@w3.org>
On Thu, Mar 25, 2004 at 03:14:53PM -0600, Dan Connolly wrote: > > On Thu, 2004-03-25 at 14:51, Rob Shearer wrote: > > A user has a large volume of data stored in a traditional RDBMS, and > > currently queries that data using SQL. > > > > The user wishes to expose an RDF view of the the database. The user > > should be able to translate his SQL queries into RDF queries with very > > little need for additional custom code. > > > > This clearly isn't really a use case in its own right; it's starting a > > level higher at the abstract requirements. > > > > Is there any support for such a requirement? > > Yes, I think so. > > We have some Semantic Web Advanced > Development experience in this area: > > http://www.w3.org/DesignIssues/RDB-RDF.html > http://www.w3.org/2000/10/swap/dbork/dbview.py > > http://www.w3.org/1999/07/13-persistant-RDF-DB > (that's what google says when I ask it about "eric rdf sql". > Is that your work on going from algae to SQL and back, ericp?) That's a somewhat obsolete look at generic triple stores. The algae implementation now uses the schema and algorithms described in Heterogeneous RDF Databases: http://www.w3.org/2003/02/15-RDF-hetro-DB/ which leans on RDF Access to Relational Databases: http://www.w3.org/2003/01/21-RDF-RDB-access/ Ie, generic triple store is simply a degenerate case of a triple store for accessing conventional (normalized) data with a generic triple store for stuff that doesn't fit into the normalized database. > That experience was one of the things that convinced the director > that it was time to standardize this stuff. We couldn't get > research funding for it any more. They said it was too straightforward, > and that industry was going to take care of that sort of > stuff pretty soon. > > Some use cases I personally have lived thru include: > > (1) a meeting registration query. see > "Aside: Fun with Relational Databases on the Semantic Web" > http://www.w3.org/2001/sw/meetings/tech-200303/ > > and > > (2) grabbing some human resources stuff out of a database. > It's in this Makefile: > > [[[ > #query the management database for resources from the Semantic Web > activity: > SWQ='http://swada.w3.org:9000/manage/.dbq?name1=Resources&fields1=ResourceID....' > > swEffort.rdf: dbview-manage > echo query is the last one... > $(WGET) $(SWQ) -O $@ > ]] -- http://www.w3.org/2001/sw/Makefile > > Hmm... I can't remember if I actually used the output of that query > for anything. > > > Is it worth working up a > > few use cases which include RDBMS schema, their RDF translations, and > > the SQL queries that we'd like to be able to translate? > > I expect so. > > -- > Dan Connolly, W3C http://www.w3.org/People/Connolly/ > see you at the WWW2004 in NY 17-22 May? -- -eric office: +81.466.49.1170 W3C, Keio Research Institute at SFC, Shonan Fujisawa Campus, Keio University, 5322 Endo, Fujisawa, Kanagawa 252-8520 JAPAN +1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA cell: +1.857.222.5741 (does not work in Asia) (eric@w3.org) Feel free to forward this message to any list for any purpose other than email address distribution.
Received on Thursday, 25 March 2004 19:30:52 UTC