Fwd: A question regarding the latest SPARQL 1.1 Proposed Recommendation

I've fixed this in the editors working draft, hoping that's the right 
thing to do.

Does this need to go on some errata list somewhere as well?

	Andy

-------- Original Message --------
Subject: A question regarding the latest SPARQL 1.1 Proposed Recommendation
Resent-Date: Thu, 13 Dec 2012 10:47:17 +0000
Resent-From: public-sparql-dev@w3.org
Date: Wed, 12 Dec 2012 08:55:12 +0100
From: Christopher Schramm <schramm@informatik.uni-luebeck.de>
To: public-sparql-dev@w3.org

Dear W3C,

i've encountered a problem while reading the SPARQL 1.1 Proposed
Recommendation of November 8.

The question i have is in regards to an example in section 9.2. The
example deals with Inverse Path Sequences and has the following example:

{
     ?x foaf:knows/^foaf:knows ?y .
     FILTER(?x != ?y)
   }


is equivalent to

   {
     ?x foaf:knows ?gen1 .
     ?gen1 foaf:knows ?y .
     FILTER(?x != ?y)
   }

However, in my opinion it should be equivalent to

   {
     ?x foaf:knows ?gen1 .
     ?y foaf:knows ?gen1 .
     FILTER(?x != ?y)
   }

Otherwise i fail to see the difference between the orgininal query and
the same query without an inversion. I would like to hear your opinion
on the matter. Moreover i have a question regarding the following query:

{
     ?x ^(foaf:a/foaf:b) ?y .
   }

I would think, that the equivalent query would be the following:

{
     ?y foaf:b ?gen1 .
     ?gen1 foaf:a ?x .
   }

Am i correct there?

Thank you for answers.

Greetings,

Christopher Schramm

Received on Friday, 14 December 2012 08:59:23 UTC