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Re: CommentResponse:JP-3

From: Axel Polleres <axel.polleres@deri.org>
Date: Wed, 2 Feb 2011 16:29:39 +0000
Cc: SPARQL Working Group <public-rdf-dawg@w3.org>
Message-Id: <7911A6EA-DB88-49CB-A3B3-C9B9C83B9817@deri.org>
To: Andy Seaborne <andy.seaborne@epimorphics.com>
Looks ok to me, I like the purchase order example, it's a very illlustrative example for multiple paths, thanks!

Axel

On 30 Jan 2011, at 19:02, Andy Seaborne wrote:

> http://www.w3.org/2009/sparql/wiki/CommentResponse:JP-3
> 
> Drafted - ready for review
> 
>  > (I've sent a version of this to Jorge offlist as discussions aren't
> possible on the comments list).
> 
> So he's seen the gist of the reply,
> 
>         Andy
> 
> On 26/01/11 14:39, Andy Seaborne wrote:
> >
> >
> > On 26/01/11 13:53, Matthew Perry wrote:
> >> I think this should work for the sum age query.
> >>
> >> SELECT SUM(?A)
> >> WHERE
> >> { ?F :age ?A
> >> { SELECT DISTINCT ?F
> >> WHERE
> >> { :me (:friend)+ ?F } }}
> >>
> >> It seems that, in general, DISTINCT will work as a there exists query
> >> when URIs and blank nodes are the endpoint of a path because we have a
> >> one-to-one mapping between URI/BN values and graph vertices, but we get
> >> a one-to-many mapping from literal values to vertices.
> >
> > Yes, that example addresses Jorge's use case and contrasts nicely with
> > the basket example where there is a need for duplicate matches from the
> > property path itself (although, in the syntax triple patterns are
> > property paths of length 1).
> >
> > Andy
> 
> 
Received on Wednesday, 2 February 2011 16:30:16 GMT

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