Re: new version of the example of RSP-QL query

Hi Emanuele & al!

Thank you for the update! Shortly quoting the attached PDF:

> Note: that this may require some resoning being the property isCloseBy symmetric.

What actually happens in the INSTANS queries<https://github.com/aaltodsg/instans/blob/master/tests/input/rsp/couplecount/couplecount_basic_v1.rq> operating under regular SPARQL semantics is that we get candidate couples matching both ways:

<someone>: Kim, <someoneElse>: Barney *and* <someone>: Barney, <someoneElse>: Kim

I'm currently taking that as a feature, because now I only need to check, if <someone> was next to yetAnotherPerson or <someone> knew <someoneElse> beforehand instead of doing the same filtering for both. In the next phase I first confirm that both symmetric solutions are still in and then filter out the other direction to avoid duplicate results:

    ?couple1 e:somebody ?somebody ;
             e:someoneElse ?someoneElse ;
             e:poi ?poi .
    ?couple2 e:somebody ?someoneElse ;
             e:someoneElse ?somebody ;
             e:poi ?poi . }
    # Remove symmetric duplicates
    FILTER NOT EXISTS { GRAPH <couples> {
      ?couple3 e:somebody ?someoneElse ;
               e:someoneElse ?somebody ;
               e:poi ?poi } }

If I removed the symmetric duplicates in the beginning, I would have to check the limiting conditions (<closeTo yetAnotherPerson> and <knows each other>) against both <someone> and <someoneElse> and the total query would likely be a bit longer.

BR,

Mikko

On 11. Dec 2014, at 12:55, Emanuele Della Valle <emanuele.dellavalle@polimi.it<mailto:emanuele.dellavalle@polimi.it>> wrote:

Dear all,

please find at the following link (and attached) the new version of the example of RSP-QL query

https://www.w3.org/community/rsp/wiki/Example_of_RSP-QL_query

I hope it covers all the discussion we had during the phone call. I’m sure it does not cover the discussion that took place over the mailing list which I haven’t found the time to read, yet.

I will try to put this new version on git hub, but I’m still confused about how to proceed there.

@Oscar, can you please explain what you had in mind?

Best Regards,

Emanuele

--
prof. Emanuele Della Valle
DEIB - Politecnico di Milano
w. http://emanueledellavalle.org <http://emanueledellavalle.org/>

<Example of RSP-QL query - RDF Stream Processing Community Group.pdf>