- From: Bijan Parsia <bparsia@isr.umd.edu>
- Date: Mon, 3 Apr 2006 11:11:44 -0400
- To: "Eric Prud'hommeaux" <eric@w3.org>
- Cc: Dan Connolly <connolly@w3.org>, RDF Data Access Working Group <public-rdf-dawg@w3.org>
On Apr 3, 2006, at 10:56 AM, Eric Prud'hommeaux wrote: [snip] > I propose the following text: > [[ http://www.w3.org/2001/sw/DataAccess/rq23/#describe > 10.4 Descriptions of Resources > > Current conventions for DESCRIBE constrain it to return an RDF > graph. You mean the specification? Isn't there reason to leave that a bit open, e.g., DESCRIBE according to CBF as HTML I.e., why put in *this* constraint (convention?)? > Future SPARQL specifications may further constrain the results > of DESCRIBE, rendering some currently valid DESCRIBE responses > invalid. > > [ Non-normative: The DESCRIBE form returns a single result RDF graph > containing RDF data about resources. This data is not prescribed by a > SPARQL query, where the query client would need to know the structure > of the RDF in the data source, but, instead, is determined by the > SPARQL query processor. The query pattern is used to create a result > set. The DESCRIBE form takes each of the resources identified in a > solution, together with any resources directly named by IRI, and > assembles a single RDF graph by taking a "description" from the target > knowledge base. The description is determined by the query service. ] > > An empty graph is a valid response to any DESCRIBE query. > ]] I don't like the non-determinism this introduces. That is, there should be a difference between not having any valid answers and just not handling DESCRIBE. Cheers, Bijan.
Received on Monday, 3 April 2006 15:11:57 UTC