ISSUE-29 (resource identifiers as strings): Require blank node and IRI identifier expressions to produce strings [R2RML]

ISSUE-29 (resource identifiers as strings): Require blank node and IRI identifier expressions to produce strings [R2RML]

http://www.w3.org/2001/sw/rdb2rdf/track/issues/29

Raised by: David McNeil
On product: R2RML

>From an implementation perspective it seems desirable to require that the expressions used to produce blank node identifiers and IRIs be of type "string". Based on my understanding of R2RML this matches the way they are expected to be used.

This allows the implementation to safely use SQL string concatenation on the blank node identifier expression to perform the "re-allocation of blank node identifiers" mentioned in the RDF spec, http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-blank-node-id .

This also removes the need to try and interpret whether a blank node created from a timestamp is the same as another blank node created from an integer (just as an example of possible type issues that arise if the expressions are not constrained to be of type string).

Received on Monday, 7 March 2011 16:10:49 UTC