- From: Steve Harris <swh@ecs.soton.ac.uk>
- Date: Sun, 4 Nov 2007 12:55:06 +0000
- To: Alan Ruttenberg <alanruttenberg@gmail.com>
- Cc: public-sparql-dev@w3.org
Well, that would be the obvious syntax for a local sub-query too. - Steve On 4 Nov 2007, at 12:48, Alan Ruttenberg wrote: > Although I intended that the specification of this was that it was > only legal for an endpoint, as that's what makes it easy. I'm not > sure it's a useful construct otherwise, as you don't need it nested > in the FROM if you have to download the file. > -Alan > > > On Nov 4, 2007, at 7:38 AM, Alan Ruttenberg wrote: > >> Good point. Perhaps FROM ENDPOINT. >> >> -Alan >> >> On Nov 4, 2007, at 7:35 AM, Steve Harris wrote: >> >>> On 4 Nov 2007, at 04:09, Alan Ruttenberg wrote: >>> >>>> This is a particularly easy one, since it adds no new >>>> expressivity. The form >>>> below can be syntactically transformed into SPARQL as specified >>>> now by way >>>> of using the SPARQL protocol for the construct in the FROM. >>>> Since this is the only reasonable way we have to do federation >>>> now, within >>>> spec, it's more like adding friendly syntactic sugar. >>> >>> As far as I can tell there's no way to tell that <http://example.com/sparql? >>> > is a SPARQL endpoint, rather that a graph served by a CGI script >>> with no arguments. >>> >>> - Steve >>> >>>> On 11/3/07, Dan Connolly <connolly@w3.org> wrote: >>>>> >>>>> Alan Ruttenberg wrote: >>>>>> >>>>>> SELECT ?a ?b >>>>>> FROM ( CONSTRUCT { ?d <b> ?b } >>>>>> FROM < http://example.com/sparql?> >>>>>> WHERE { ?b <b> ?d } ) >>>>>> WHERE { ?a <b> ?b } >>>>> >>>>> >>>>> Yes... the Data Access WG considered this sort of thing briefly; >>>>> we didn't see any particular reason not to do it but we... >>>>> >>>>> RESOLVED 2005-01-20: to postpone cascadedQueries; while >>>>> federation use >>>>> cases are interesting, the designs don't seem mature and the use >>>>> cases >>>>> are not urgent; with KendallC abstaining. >>>>> http://www.w3.org/2001/sw/DataAccess/issues#cascadedQueries >>>>> >>>>> I'm happy to see people playing around with it; I hope the >>>>> designs get mature soonish. >>>>> >>>>> >>>>> -- >>>>> Dan Connolly, W3C http://www.w3.org/People/Connolly/ >>>>> >>>>> >>> >> >
Received on Sunday, 4 November 2007 12:55:27 UTC