We present a new approach to implement an object bitempo-ral database where both valid-time and transaction-time are represented. It is based on the DataBase Version model, which allows an eecient management of object versions. This facilitates the manipulation of past events and allows a straightforward representation of branching evolution in valid-time.

A temporal database schema models objects or concepts with time-related or time-variant properties and a derived database contains measurements or descriptions concerning these temporal properties. The modelling of temporal information in a temporal database has an impact on the consistency of the database. Of course, this temporal information can be queried. In some cases, information in the q...

In data warehouses measures are analyzed along different dimensions. Although the structures of these dimensions change over time, data warehouse tools currently in use are not able to deal with these modifications in a sophisticated way. In this paper we present a bitemporal extension of the COMET metamodel. This extension enables us to represent not only the valid time of structural modificat...