This bug report is an element of this one, for needed metaproperties:

https://bugzilla.wikimedia.org/show_bug.cgi?id=30610

and it is a blocker for this one, for existence and uniqueness validation:

https://bugzilla.wikimedia.org/show_bug.cgi?id=30537

Without a creation date property, it is not currently possible to use a workaround to check for duplicates without also marking the original as a duplicate. Being able to find the oldest page creation date makes it possible to allow that original page to not be marked as a duplicate, while all subsequent pages are marked as duplicates.

An inaccurate manually created page creation date property can be employed as a workaround for the problem, but it is only able to record the date that the form was loaded, not the actual creation date of the resulting page produced by the form.

In order to do this for all pages, as reported in bug 30537, a creation date metaproperty is required, and very probably should be in SMW core instead of an extension, due to its "blocker" nature.

Once a creation date metaproperty becomes available in the core, bug 30537 can be fixed.

Version: unspecified
Severity: blocker