$uri as String
) as Number?
Returns timestamp of the most recent visible update to a
document, lock, or property.
Returns the empty sequence if no document, lock, or property
The URI of the document, lock, or property.
If the current request is part of a multi-statement transaction and
the most recent visible update was in an earlier statement in the
transaction, the timestamp for the update has not yet been established,
so an empty sequence is returned.