W3C home > Mailing lists > Public > public-rdf-dawg@w3.org > October to December 2011

Re: draft response JBolleman-1, JBolleman-2

From: Axel Polleres <axel.polleres@deri.org>
Date: Mon, 17 Oct 2011 22:21:41 +0200
Cc: <public-rdf-dawg@w3.org>
Message-Id: <C3908C14-5066-43D5-9A9D-00586EA74562@deri.org>
To: Andy Seaborne <andy.seaborne@epimorphics.com>
Updated with the link to http://www.w3.org/TR/sparql11-query/#modOrderBy as suggested.

best,
Axel

On 17 Oct 2011, at 22:16, Andy Seaborne wrote:

> 
> 
> On 17/10/11 20:19, Axel Polleres wrote:
> > Andy, all,
> >
> > I have adapted the response draft for Jerven Bolleman (essentially incorporating your arguments), see
> >   http://www.w3.org/2009/sparql/wiki/CommentResponse:JBolleman-1
> >
> > Please check especially the following (I wasn't 100% sure what you meant by
> >> By the way, an "ORDER BY *" is still not a gauaranteed total ordering.
> > but I guess it was in spirit this:
> >   --------
> > First of all, note that a shortcut like "ORDER BY *" as you suggest would not guarantee a predicable total order of results (for instance when blank nodes are returned, since two separate calls are not guaranteed to return the same blank node identifiers).
> >   --------
> 
> While its's true that bNodes don't sort predictably, there are more
> important and significant cases though that would matter:
> Why not refer to the text in:
> 
> http://www.w3.org/TR/sparql11-query/#modOrderBy
> 
> (which is SPARQL 1.0 text)
> 
>         Andy
> 
> >
> > I just see Jerven asking about the state of his comment (will answer him offlist that we're at it, but I'd appreciate feedback to get this oune out quickly
> 
> 
> >
> > thanks a lot,
> > Axel
> >
> >
> > On 17 May 2011, at 17:41, Andy Seaborne wrote:
> >
> >>
> >>
> >> On 17/05/11 13:40, Axel Polleres wrote:
> >>> Hi all,
> >>>
> >>> drafted a response to
> >>>
> >>>    http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2011May/0016.html
> >>>    http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2011May/0017.html
> >>>
> >>> at
> >>>    http://www.w3.org/2009/sparql/wiki/CommentResponse:JBolleman-1
> >>>
> >>> please check/acknowledge
> >>>
> >>> thanks,
> >>> Axel
> >>
> >> We did consider things in this area [1] and so we can say we actively
> >> were aware of the issue and choose, on time resource issue grounds, not
> >> to address the matter. (voting record?)
> >>
> >> [1]  http://www.w3.org/2009/sparql/wiki/Feature:Cursors
> >>
> >> Let's at least say this is a protocol issue not a query issue.  Existing
> >> HTTP mechanisms are applicable like ETags for consistency and ranges for
> >> slicing. Client side paging off a stream of results is also a candidate
> >> mechanism.
> >>
> >> Cursors, paging, (transactions) etc are about controlling the flow of
> >> results and about results over multiple requests, not in defining results.
> >>
> >> I think this clear-cut separation is important because it then can
> >> address interactions with update, system restarts and anything that
> >> means the server would loose state or simple re-execution of the query
> >> would produce different answers even in a deterministic query processor.
> >>
> >> By the way, an "ORDER BY *" is still not a gauaranteed total ordering.
> >>
> >>          Andy
> >>
> >>
> >
> 
Received on Monday, 17 October 2011 20:22:22 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:15:46 GMT