R2RML Linked Data Aspects

Hi all,

As per our discussion during the last telco I wanted to draw our
attention again on the Linked Data aspects of R2RML [1].

We should definitely not repeat the Linked Data principles in R2RML, but
make clear, how certain Linked Data aspects can be dealt with and where
problems would potentially occur.

I see in particular the following three issues:

1. *identifier generation* - three possible approaches were outlined in
[2], from my POV in particular the first ("Direct representation of
entity references in database columns") and and third one ("Defining an
entity mapping table") make sense, since they are easy to implement and
would also allow reverse translations.

2. *namespaces* - I could not find any possibility to declare namespaces
and respective prefixes in the current draft. is that left out
intentionally? If not, we should add a respective declaration and make
clear, that only namespaces which are governed by the user creating the
mapping can be made de-referencable later on for Linked Data publishing.

3. *blank nodes* - we should make clear, that wherever blank nodes might
be generated by any R2RML feature, this will result that the respective
resources can not be directly de-referenced.

There might be more aspects to be considered in order to make R2RML
Linked Data proof, but this is what comes to my mind for now. Maybe
others can comment on that.

After we have a clear picture, we can think how this can be best
reflected by the R2RML draft.

Best,

Sören

[1] http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects
[2] http://www.w3.org/2001/sw/rdb2rdf/wiki/Entity_disambiguation

Received on Monday, 14 March 2011 16:52:12 UTC