Re: Start discussion

On Sun, Mar 21, 2010 at 11:49 PM, Ezzat, Ahmed <Ahmed.Ezzat@hp.com> wrote:

>
> Hi Juan,
>
> We have tasks for the use case.  I agree that I do not see enough
> discussion on the distribution list. It was agreed on we need the use case
> completed before diving deeper in the mapping language. This Tuesday let us
> discuss what is left on the use case. Our highest priority is to finalize
> what the team will be delivering sometime in April - higher priority than
> the semantics of the language.
>

Great to know. I agree that we should get the use cases out the door asap.
I'm trying to do my share :)

>
> I agree for using Datalog in expressing the semantics of the mapping
> language; we should discuss that in the group. If I remember correctly, Andy
> Seaborne used Datalog in expressing the semantics of some SPARQL language
> constructs in the SPARQL WG...
>

+1

>
> Lee, Independent of which approach you use, you need to validate the
> semantics of the mew language.  Advantage of Datalog, as it is based on
> logic, it is more expressive than relational algebra. Below is few pages
> about Datalog.
>

Great set of slides. I honestly think that using datalog to define the
semantics should easy and we have a great team to get it done :)

>
>
> Regards,
>
> Ahmed
>
>
>
> -----Original Message-----
> From: public-rdb2rdf-wg-request@w3.org [
> mailto:public-rdb2rdf-wg-request@w3.org <public-rdb2rdf-wg-request@w3.org>]
> On Behalf Of Lee Feigenbaum
> Sent: Sunday, March 21, 2010 5:51 PM
> To: Juan Sequeda
> Cc: public-rdb2rdf-wg@w3.org
> Subject: Re: Start discussion
>
> On 3/21/2010 8:26 PM, Juan Sequeda wrote:
> > Hi Everybody,
> >
> > There has been no discussion at all on the list, and that honestly
> > worries me.
>
> I share this concern, which is one reason that I decided to join the
> group and try to add what I can.
>
> > I know that we need to have a Use Case documents, but it is not
> > completely clear to me what else we need to turn in and by when.
> >
> > One issue that I personally feel than needs to be settled is the
> > semantics of the language. One we have this defined, it is just a matter
> > of deciding on what is the syntax. I don't think we have made much
> > progress on this issue. I have proposed to develop the semantics of the
> > mapping language in datalog. I'd be up for working on this in
> > conjunction with Marcelo Arenas and Dan Miranker.
>
> Ideally, I'd hope that the semantics of the language follow from the
> requirements which follow from the use cases.
>
> As far as datalog, I know next to nothing about it, so my questions are
> probably naive. Is there a datalog standard that we will be able to
> normatively reference if the semantics of the language are given in
> datalog?
>
> Also, I'm not sure if separating the syntax & semantics is definitely an
> easy thing to do. I know that there are people on the group who advocate
> that the mapping language be based on SPARQL CONSTRUCT queries combined
> with a default mapping from the relational model to the RDF model. In
> this case, I imagine it would make more sense to lean on the SPARQL
> algebra/semantics?
>
> Lee
>
> > What else should we be having discussions on? The clock is ticking.
> >
> >
> > Juan Sequeda
> > +1-575-SEQ-UEDA
> > www.juansequeda.com <http://www.juansequeda.com>
>
>
>