A temporal natural join is a binary operator that generalizes the snapshot natural join to incorporate one or more time dimensions. Tuples in a temporal natural join are merged if their explicit join attribute values match, and they are temporally coincident in the given time dimensions. As in the snapshot natural join, the relation schema resulting from a temporal natural join is the union of the explicit attribute values present in both operand schemas, along with one or more timestamps. The value of a result timestamp is the temporal intersection of the input timestamps, that is, the chronons contained in both.