Re: Pre-CR review - Section 4 comments

Richard - Thanks for your response.

On Mon, Jan 23, 2012 at 10:47 AM, Richard Cyganiak <richard@cyganiak.de>wrote:

> On 23 Jan 2012, at 15:32, David McNeil wrote:
> > * My last call comment on this still stands: Doesn't this definition of
> a mandatory error contradict our stated intent of: if data values fall
> outside of the intersection of SQL data types and XSD data types then the
> behavior is undefined (but throwing an error is not required)?
>
> Are you referring to this?
>
> [[
> The following conditions give rise to data errors: […] A term map that has
> a validatable RDF datatype as its specified datatype produces an ill-typed
> literal.
> ]]
>
>
Yes.


> > I don't remember seeing a place in the spec that captures our intent
> regarding the intersection of SQL and XSD data types.
>
>
> That intent was about which SQL types to handle in the natural mapping
> from SQL values to RDF literals. This is captured in Section 10.2 – it only
> handles the intersection of Core SQL 2008 and XSD.
>

Hmm... I thought the intent was to cover the data values.

The scenario I have in mind is:

TS is a SQL data type that maps to TX, an XSD data type.

The domain of valid values for TS is DS. The domain of valid values for TX
is DX.

My understanding was that our intent for R2RML was to only define what
happens for SQL data values of type TS that fall in the intersection of DS
and DX.

Meaning that if a SQL data value of type TS had no valid representation in
DX then the behavior of the mapping was undefined. In this case the R2RML
processor could produce a data value which was outside of DX.

-David