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RE: DISTINCT()

From: Polleres, Axel <axel.polleres@siemens.com>
Date: Wed, 14 Mar 2012 11:37:49 +0100
To: Andy Seaborne <andy.seaborne@epimorphics.com>, "public-rdf-dawg@w3.org" <public-rdf-dawg@w3.org>
Message-ID: <9DA51FFE5E84464082D7A089342DEEE80137B3693F2D@ATVIES9917WMSX.ww300.siemens.net>
> Could you expand on "we need DISTINCT"?  Is that just a 
> technical point that DISTINCT covers more or a political 
> point about the comments?

I think it is a technical point, since a DISTINCT-paths semantics 
which can be efficiently implemented by DISTINCT subqueries alone,
at least not trvially...

While I do think that DISTINCT() can possibly 
be defined in terms of a rewriting which introduces fresh variables for blank nodes

 
-- 
Dr. Axel Polleres 
Siemens AG Österreich 
Corporate Technology Central Eastern Europe Research & Technologies 
CT T CEE 
 
Tel.: +43 (0) 51707-36983 
Mobile: +43 (0) 664 88550859
Fax: +43 (0) 51707-56682 mailto:axel.polleres@siemens.com 
 

> -----Original Message-----
> From: Andy Seaborne [mailto:andy.seaborne@epimorphics.com] 
> Sent: 14 March 2012 11:02
> To: public-rdf-dawg@w3.org
> Subject: Re: DISTINCT()
> 
> On 14/03/12 09:48, Polleres, Axel wrote:
> > Just my two cents to emphasize that I tend to agree on 
> that: I believe 
> > we need DISTINCT() to address JC-4 and related comments in 
> a fashion 
> > agreeable to the commenters.
> 
> Could you expand on "we need DISTINCT"?  Is that just a 
> technical point that DISTINCT covers more or a political 
> point about the comments?
> 
> What about the lesser case of just {*}{+} and *+ changes?
> 
> 	Andy
> 
> 
Received on Wednesday, 14 March 2012 10:38:23 GMT

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