ISSUE-20 (predicate/object refer to joined table): Allow a predicate/object map to reference a joined table. [R2RML]

ISSUE-20 (predicate/object refer to joined table): Allow a predicate/object map to reference a joined table. [R2RML]

http://www.w3.org/2001/sw/rdb2rdf/track/issues/20

Raised by: David McNeil
On product: R2RML

Allow a predicate/object map to reference a joined table.

RefPredicateObjectMaps allow the logical tables under TriplesMaps to be "joined". But they do not allow the expressions used to compute the predicate or
object to refer to the parent's logical table.

This can be worked around by creating a new SQL query that performs the necessary join and using this to produce the subject, predicate, and object. However, this requires undesirable copying of the SQL.

This could be addressed by allowing a predicate object map to explicitly
specify a logical table to join to the TriplesMaps logical table.

Received on Tuesday, 1 February 2011 19:31:46 UTC