Re: please read before participating in translation scheme debate [Re: Translating DB values to RDF terms using 1) R2RML views and 2) using R2RML-native translation scheme]

On 12/14/11 8:51 PM, Souripriya Das wrote:
> Kingsley,
>
> I agree fully with you about the power of views. In fact that was the 
> point I was trying to emphasize. Such views, besides regular tables, 
> are indeed the targets of R2RML. Use of views (or more specifically, 
> queries or view definitions) are sufficient to specify unrestricted 
> translation as illustrated in Examples 1 and 2 in 
> http://www.w3.org/2001/sw/rdb2rdf/wiki/Translating_Database_Values_to_RDF_Terms
>
> Note that the main reason we have introduced constructs in R2RML for 
> specifying "R2RML views" (sql query string), instead of relying solely 
> on traditional DB views, is to allow mapping avoiding any privilege 
> issues regarding DB view creation in the host database (e.g., if the 
> host database is Read-Only).
Okay.

I am eager to make a test between Oracle (directly) and Virtuoso 
fronting Oracle re. R2RML payload exchange, putting all of this through 
the grinder :-)

Kingsley
>
> Thanks,
> - Souri.
>
> ----- Original Message -----
> From: kidehen@openlinksw.com
> To: public-rdb2rdf-wg@w3.org
> Sent: Wednesday, December 14, 2011 5:43:51 PM GMT -05:00 US/Canada Eastern
> Subject: Re: please read before participating in translation scheme 
> debate    [Re: Translating DB values to RDF terms using 1) R2RML views 
> and 2) using    R2RML-native translation scheme]
>
> On 12/14/11 4:44 PM, Souripriya Das wrote:
>
>     Has anybody else looked at the "R2RML view" based translation
>     scheme and examples in
>     http://www.w3.org/2001/sw/rdb2rdf/wiki/Translating_Database_Values_to_RDF_Terms
>
>     If not, please do. I'd very interested in what you think about use
>     of just R2RML views for specifying translation info.
>     The power of "R2RML views" may be sufficient in practice.
>
>     Thanks,
>     - Souri.
>
> Souri,
>
> Can't that same SQL statement be used to create normal SQL View that's 
> simply treated like a Table re. R2RML mapping? We support those 
> constructs in SQL and that's exactly what we recommend to our users 
> i.e., use the RDBMS engines SQL sophistication to create Views that 
> are then treated like Tables when it comes to the RDF Views mappings. 
> The same even applies to Stored Procedures which can also be treated 
> as Views.
>
> Our own native RDF Views language offers exactly the same thing using 
> different syntax. Thus, for compatibility sake re., interchange of 
> R2RML documents, it's best to localize DBMS specific functionality 
> thereby making conventional SQL Views (transient of materialized) or 
> Tables the targets of R2RML mappings.
>
> Fundamentally, there's no reason why we shouldn't be able to exchange 
> an R2RML map with you and vice versa. Ditto anyone else that supports 
> R2RML. Simple scenario:
>
> 1. I attach Oracle to Virtuoso via and ODBC or JDBC data source name (DSN)
> 2. I generate a native RDF View based on the attached table
> 3. I export the RDF Views definitions via an R2RML mapping doc
> 4. Publish to a URL
> 5. You HTTP GET the resource at the aforementioned URL
> 6. Run it through your R2RML processor.
> 7. We end up with Resource URIs in different Data Spaces that expose 
> the same data.
>
> 1-7 is my basic acid test for R2ML when implementations become official.
>
> -- 
>
> Regards,
>
> Kingsley Idehen 
> Founder&  CEO
> OpenLink Software
> Company Web:http://www.openlinksw.com
> Personal Weblog:http://www.openlinksw.com/blog/~kidehen
> Twitter/Identi.ca handle: @kidehen
> Google+ Profile:https://plus.google.com/112399767740508618350/about
> LinkedIn Profile:http://www.linkedin.com/in/kidehen
>
>
>
>


-- 

Regards,

Kingsley Idehen 
Founder&  CEO
OpenLink Software
Company Web: http://www.openlinksw.com
Personal Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca handle: @kidehen
Google+ Profile: https://plus.google.com/112399767740508618350/about
LinkedIn Profile: http://www.linkedin.com/in/kidehen