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Re: how to specify that in SERVICE VAR how we query all possible sparql endpoints

From: Carlos Buil Aranda <cbuil@fi.upm.es>
Date: Sun, 31 Jul 2011 20:50:11 -0400
Message-ID: <4E35F843.7050606@fi.upm.es>
To: Andy Seaborne <andy.seaborne@epimorphics.com>
CC: public-rdf-dawg@w3.org
  Thanks for your comments Andy,

I just applied and uploaded them to the CVS.

cheers,

Carlos

On 29/07/2011 8:50, Andy Seaborne wrote:
> Comments on v1.65.
>
> Overall:
>
> 1/ the SERVICE/BINDINGS relationship example needs changing - 
> suggestion below.
>
> 2/ Some editorial things in passing.
>
> Other than that, it looks good-to-go to me.
>
>     Andy
>
>
> ** Abstract
>
> s/of a SPARQL/of SPARQL/
>
> ** Intro
>
> "consumers" -> "data consumers"
>
> "joined with results" -> "combined with results"
>
> Both are correct but at this level, join seems a bit techy.
>
> s/.././ at end of para.
>
> ** 2.2
>
> "Data in default" -> "Data in the default"
> "and data in default" -> "and data in the default"
>
> ** 2.3
> "SILENT token" -> "SILENT keyword"
> token a feature of parsing
>
> ** 2.4
> "BINDINGS" -> "<tt>BINDINGS</tt>"
>
> "SERVICE and BINDINGS are combined"
> ->
> "SERVICE and BINDINGS can work together"
>
>
> Example:
> (this is a rough outline and needs editing to fit it into the document)
> [NB: No BINDINGS no OPTIONAL in the top level query]
>
>
> Suppose we have the query:
>
> PREFIX : <http://example.org/>
> PREFIX foaf: <http://xmlns.com/foaf/0.1/>
> SELECT ?s ?o
> {
>   ?s a foaf:Person
>   SERVICE <http://example.org/sparql> {?s foaf:knows ?o }
> }
>
> [NB: No BINDINGS no OPTIONAL.
>
> An implementation may choose to execute this as:
>
> 1/ Determine that "?s a foaf:Person" has 3 answers, :a :b :c
>
> 2/ Instead of asking {?s foaf:knows ?o } at the remote endpoint, it 
> restricts ?s by using BINDINGS:
>
> PREFIX : <http://example.org/>
> PREFIX foaf: <http://xmlns.com/foaf/0.1/>
> SELECT *
> {
>   ?s foaf:knows ?o
> } BINDINGS ?s { (:a) (:b) (:c) }
>
> If <http://example.org/sparql> contains a very large database,  {?s 
> foaf:knows ?o } may result in very large set of results.  By passing 
> over restricts for :s, the query process involding SERVICE limits the 
> data returned to the data it needs for the overall query.
>
>     Andy
>
>
>
>
>
Received on Sunday, 31 July 2011 20:50:39 GMT

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