Re: D2RQ and Revelytix semantics

Boris,

I think it's time for me to put this on the wiki (hopefully it will be
easy). I'll do it tomorrow after the call. When it's on the wiki then please
add the R2O mapping language!

Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com


On Mon, Jul 26, 2010 at 7:06 PM, Boris Villazón-Terrazas <
boris.villazon@deri.org> wrote:

>  Hi Juan
>
> Good analysis.
> I just want to point out that the R2O mapping language [1] follows the same
> philosophy of the D2RQ. It is database-instance-only and is XML-based.
> I can include the R2O examples in your document if you want. Maybe it would
> be good for comparison purposes.
>
> Looking forward to Alex's presentation .
>
> Boris
>
>
> [1] http://www.cs.man.ac.uk/~ocorcho/documents/SWDB2004_BarrasaEtAl.pdf
>
>
> Juan Sequeda wrote:
>
> Hi Richard, Alex and all
>
>  I took the liberty of analyzing D2RQ and Revelytix mapping language and
> compare it to the semantics that Marcelo and I have defined in Datalog [1].
> (BTW, Marcelo defined the semantics of Datalog in the wiki also!)
>
>  Marcelo and I are still working on this so you can see a draft of what we
> are doing in the following google doc (once we are done, we will put it on
> the wiki.... tables in the wiki are a pain!)
>
>
> https://docs.google.com/document/pub?id=1APTqD2lJLRjwV6gmPKqDRqC3aT8bozHF0udIXndMNWQ
>
>
>  Please forgive me if I butchered the mapping language.
>
>  Quick conclusion:
>
>  - Both mapping languages are very similar
> - Both mapping languages have the semantics established as
> Database-Instance-and-Schema Mapping [1] (there is a definition of Classes
> and Properties). There is no way to formally prove this because both
> languages don't have existing defined semantics (right?)
> - Revelytix language has different ways of saying the same thing for sake
> of query optimization ( right?). (I personally believe this is something we
> should avoid. Language and implementation details should be separate... just
> look at SQL)
>
>  Looking forward to Alex's presentation tomorrow!
>
>
>  [1]
> http://www.w3.org/2001/sw/rdb2rdf/wiki/Database-Instance-Only_and_Database-Instances-and-Schema_Mapping
>
> Juan Sequeda
> +1-575-SEQ-UEDA
> www.juansequeda.com
>
>
>