- From: Dan Connolly <connolly@w3.org>
- Date: Thu, 18 Mar 2004 12:01:33 -0600
- To: Kendall Clark <kendall@monkeyfist.com>
- Cc: RDF Data Access Working Group <public-rdf-dawg@w3.org>
On Thu, 2004-03-18 at 11:01, Kendall Clark wrote: > -- Name -- > > Generically discover/publish server capabilities > > -- Description -- > > Abelard often needs to query an arbitrary list of RDF storage servers > for assertions about a set of URIs he cares about. Abelard... great name... now... why does he care about these URIs? What life persuit/business is he in? What's his role? Is he an IT application designer? A web site designer? A financial analyst? A plumber? Can we find something less technical than "capability discovery" to label this use case with? I think you've done a good job of motivating a requirement around preserving an investment in extant data access mechanisms. But I'd like the story to start with something more real-world than "an arbitrary list of RDF storage servers". > Abelard's client > software includes support for three different query > languages. Abelard's client software connects to each RDF storage > server and determines whether it supports one of the three query > languages it knows about. Abelard's client software chooses, based on > priorities set by Abelard, to send different queries to different > servers. > > Heloise makes RDF available over the Web using an RDF storage > server. Heloise's server, implementing DAWG, supports the DAWG query > language; but it also supports the Versa[1] RDF path query > language. Heloise's server makes its query language capabilities > available in a machine readable form. It negotiates with clients in > order to choose the most appropriate query language that they have in > common. > > -- Value -- > > Abelard can formulate queries in a variety of query languages, which > preserves his existing investment. Abelard's software vendor and > Heloise's software vendor can develop and sell extensible, relatively > generic systems. > > Abelard and Heloise are able to exchange data in an interoperable > fashion without requiring out-of-band, human negotiation about > capabilities. > > -- Other -- > > Rather than writing several parallel use cases just like this one, I > invite the reader to substite the following for "query languages" in > this use case: > > * RDF serialization types > * context support > * publicly available models with read access > * publicly available models with write access > > Footnotes: > [1] http://uche.ogbuji.net/tech/rdf/versa -- Dan Connolly, W3C http://www.w3.org/People/Connolly/ see you at the WWW2004 in NY 17-22 May?
Received on Thursday, 18 March 2004 13:01:30 UTC