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Re: test cases for fromUnionQuery, please

From: Yoshio FUKUSHIGE <fuku@w3.org>
Date: Thu, 2 Jun 2005 17:54:44 +0900
Message-ID: <003d01c56750$b9343c20$f1e41b85@steelball>
To: "Steve Harris" <S.W.Harris@ecs.soton.ac.uk>, "RDF Data Access Working Group" <public-rdf-dawg@w3.org>

Ah! you are right, Steve,which enhances the simplicity of my proposal.

Best,
Yoshio
fukushige.yoshio@jp.panasonic.com
fuku@jp.panasonic.com

----- Original Message ----- 
From: "Steve Harris" <S.W.Harris@ecs.soton.ac.uk>
To: "RDF Data Access Working Group" <public-rdf-dawg@w3.org>
Sent: Thursday, June 02, 2005 5:44 PM
Subject: Re: test cases for fromUnionQuery, please


> 
> On Thu, Jun 02, 2005 at 01:48:58AM -0400, Eric Prud'hommeaux wrote:
>> Recording Yoshio and my whiteboard discussion here:
>> 
>> Given this data:
>>   <c>:
>> <A> knows <B>
>> 
>>   <d>:
>> <B> mbox <mailto:b>
>> 
>> It seems the following 4 expressions are all equivilent:
>> 
>> (1) (Named Graphs (arbitrary pre-existing data)):
>>   FROM <c> <d>
>>   WHERE {
>> GRAPH ?g { ?who knows ?whom } .
>> GRAPH ?g { ?whom mbox ?mbox } .
>> FILTER ?g = <c> || ?g = <d>
>> 
>> (2) (Source (arbitrary pre-existing data)):
>>   FROM <c> <d>
>>   WHERE {
>> SOURCE ?g { ?who knows ?whom } .
>> SOURCE ?g { ?whom mbox ?mbox } .
>> FILTER ?g = <c> || ?g = <d>
>> 
>> (3) (No Default Graph): 
>>   FROM <c> <d>
>>   WHERE {
>> ?who knows ?whom .
>> ?whom mbox ?mbox } }
>> 
>> (?) (Source + CLEAR (arbitrary pre-existing data)):
>>   CLEAR
>>   FROM <c> <d>
>>   WHERE {
>> ?who knows ?whom .
>> ?whom mbox ?mbox } }
> 
> I dont believe so, wouldn't
> 
> FROM <c> <d>
> WHERE {
>     ?who knows ?whom .
>     ?whom mbox ?mbox }
> 
> Be equivalent to
> 
> FROM <c> <d>
> WHERE {
>   SOURCE ?g1 { ?who knows ?whom } .
>   SOURCE ?g2 { ?whom mbox ?mbox } . 
>   FILTER ?g1 = <c> || ?g1 = <d> &&
>          ?g2 = <c> || ?g2 = <d> }
> 
> - Steve 
> 
>
Received on Thursday, 2 June 2005 08:54:47 GMT

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