- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Tue, 11 May 2004 15:01:56 +0100
- To: "'Steve Harris'" <S.W.Harris@ecs.soton.ac.uk>, <public-rdf-dawg@w3.org>
Farrukh, Steve, I understood "3.10 Result Limits" to be about having LIMIT in queries, that is "get a maximum of N results even if there are more", not cursors and chunking nor OFFSET. We had the requirement: """ from the F2F: The query language/protocol supports limit, offset and ordering of results. """ But it didn't get as much support. It got 5 yes, 3 no: whereas just "limit" got 9/2. OFFSET is problematic in RDF (no ordering) and also gets into stability of the result sets over a period of time which is difficult in a federated, web environment. The phrase "fetching it in chunks" still seems to be cursors to my reading. Farrukh - Could you say some more about your experience with ebXML Registry etc? It is a problem if the results are large - just as if a web page is a large PDF or a database backed URL generates huge amounts of HTML. It just that machine processing makes it worse as they don't hit the "stop" button. Andy -------- Original Message -------- > From: public-rdf-dawg-request@w3.org <> > Date: 11 May 2004 14:12 > > On Tue, May 11, 2004 at 09:04:03 -0400, Farrukh Najmi wrote: > > 3.10 Result Limits > > I think this requirement should be replaced with a requirement for a > > database cursor like requirement. This is essential for scalability > > according to my experience with ebXML Registry etc. > > Cursors are explictly utside the charter: > http://www.w3.org/2003/12/swa/dawg-> charter#protocol > > but > > > > 3.10 Iterative Query Support > > The > query language or protocol must be able to handle large result > > sets > > of any size by iterating over the result set and fetching it in > > chunks. > > this seems reasonable and does not require cursors, per se. > > To me the important distinction is that cursors require sone > inter-query state, whereas limit and offset are explictly coded into > the query. > > - Steve
Received on Tuesday, 11 May 2004 10:03:23 UTC