- From: Howard Katz <howardk@fatdog.com>
- Date: Fri, 16 Apr 2004 07:54:06 -0700
- To: "Eric Prud'hommeaux" <eric@w3.org>
- Cc: "RDF Data Access Working Group" <public-rdf-dawg@w3.org>
> I can't speak to Andy's agenda, but one point that's been kicking > around in the XQuery/RDF Query arena for a while is that XQuery can be > used to express SQL queries so it must be able to express RDF > queries. It can, if you're able to work out a mapping from the RDF data model into the XQuery data model, which is basically the XML Infoset + XML Schema support + support for multiple documents. I'm finding myself quite interested in the inverse problem: would it be possible and useful to be able to map from the XQuery surface language into an underlying RDF graph-based data model, so that XQuery syntax can be used to interrogate an RDF data store more or less directly? In other words, can we swap out XQuery's underlying XML-based data model and slide in an RDF-based one in its place so that we don't have to do the mapping to XML? I'll be talking about this after Amsterdam. > I've seen a couple approaches that I believe workable [1] > [2], but would like to see how people solve the problem for SQL. I've given a few pointers in my response to Andy's email re SQL-to-XML mappings for XQuery. > I suspect that in standardizing an RDF query language we are going > beyond where existing SQL mappings to XQuery have gone in that we want > *one* mapping to XQuery that operates on XQuery+whatever > implementations from different vendors. Does such a "standard" mapping > to SQL exist? I'm not sure what you mean by the last, Eric. Can you explain a bit more? Howard > [1] http://www.w3.org/2001/11/13-RDF-Query-Rules/#XQueryFA > [2] http://www.w3.org/2001/11/13-RDF-Query-Rules/#TreeHugger > -- > -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 Friday, 16 April 2004 10:52:56 UTC