Re: A question regarding the latest SPARQL 1.1 Proposed Recommendation

On 12/12/12 07:55, Christopher Schramm wrote:
 > Am i correct there?


Yes - it's a mistake in the document.  Now fixed in the editors working 
draft.

	Thanks
	Andy	


> 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 08:57:55 UTC