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RE: test cases for fromUnionQuery, please

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Thu, 2 Jun 2005 11:17:01 +0100
Message-ID: <8D5B24B83C6A2E4B9E7EE5FA82627DC9C19540@sdcexcea01.emea.cpqcorp.net>
To: "Steve Harris" <S.W.Harris@ecs.soton.ac.uk>, "RDF Data Access Working Group" <public-rdf-dawg@w3.org>




-------- Original Message --------
> From: Steve Harris <>
> Date: 2 June 2005 09:45
> 
> 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

And, if I understand this correctly, a step further,

FROM NAMED <c>
FROM NAMED <d>
WHERE {
 	GRAPH ?g { ?who knows ?whom } .
 	GRAPH ?g { ?whom mbox ?mbox } .
    	FILTER ?g = <c> || ?g = <d>
      }

??

	Andy
Received on Thursday, 2 June 2005 10:17:10 GMT

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