- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Sat, 5 Dec 2009 17:28:56 -0500
- To: public-rdb2rdf-wg@w3.org, Alexandre Bertails <bertails@w3.org>
er, perhaps a pointer would be helpful
http://www.w3.org/2009/Talks/1215-SWObjects-egp/
* Eric Prud'hommeaux <eric@w3.org> [2009-12-05 17:16-0500]
> I'll be working on this more, but here's a start on the slides
> introducing algebra for RDB->RDF and (corresponding) SPARQL->SQL
> mappings. If folks want to play with this stuff, try downloading
> the appropriate SPARQL from
> http://sourceforge.net/projects/swobjects/files/
> and executing "SPARQL -s http://hr.example/DB/ -e
> "PREFIX emplP: <http://hr.example/DB/Employee#>
> SELECT ?empName ?managName
> WHERE { ?emp emplP:lastName ?empName .
> ?emp emplP:manager ?manager .
> ?manager emplP:lastName ?managName }"
>
> You should see:
>
> SELECT emp.lastName AS empName, manager.lastName AS managName
> FROM Employee AS emp
> INNER JOIN Employee AS manager ON manager.id=emp.manager
>
> which corresponds closely (modulo NULLs) to the results expected in
> http://www.w3.org/2008/07/MappingRules/StemMapping#bgp1
>
> The pitch is that this is a doable and useful task and that the world
> will buy us many beers for accomplishing this.
> --
> -ericP
--
-ericP
Received on Saturday, 5 December 2009 22:29:40 UTC