On 3 June 2015 at 12:48, Andrew Gray andrew.gray@dunelm.org.uk wrote:
The lack of deduplication is probably intentional rather than a bug, and both entries are "correct". Perhaps one way to handle this for Wikidata would be to, hmm, say something like "if the item is some kind of a bridge, then allow two IDs" in the constraints?
The constraint should be "usually one ID" (i.e. "SHOULD only have one ID), not "MUST have only one ID.
Wikidata already allows for this, and the constraints are editable.
See also the talk page and report for P496 for an example of a listed exception.