Fully temporal relation; Temporal relation; Valid-time and transaction-time relation
A bitemporal relation captures exactly one valid time aspect and one transaction time aspect of the data it contains. This relation inherits its properties from valid-time relations and transaction-time relations. There are no restrictions as to how either of these temporal aspects may be incorporated into the tuples.
In this definition, “bi” refers to the capture of exactly two temporal aspects. An alternative definition states that a bitemporal relation captures one or more valid times and one or more transaction times. In this definition, “bi” refers to the existence of exactly two types of times.
One may adopt the view that the data in a relation represents a collection of logical statements, i.e., statements that can be assigned a truth values. The valid times of these so-called facts are the times when these are true in the reality modeled by the relation. In cases...