We evaluate a model for temporal data utilizing the benefits of object-relational database systems (ORDBS). In particular we show how attribute timestamping can be efficiently implemented in state-of-the-art ORDBS. The attribute timestamping concept is based on introducing user-specific types for temporal versions of datatypes. Moreover on the physical level we make use of user-defined index structures; in particular adapted spatial indexes based on generalized search trees are applied. These index structures greatly improve performance of important operators on both valid and bitemporal datatypes and show the effectiveness of this approach.

Methods for deriving constraint maintaining triggers from dynamic integrity constraints represented by transition graphs are presented. The methods reduce integrity monitoring to checking changing static conditions according to life cycle situations. Thus, triggers have to be generated from these graphs, which depend not only on the operations that have occurred in a transaction, but also on the situations that have been reached by the objects mentioned in the constraints. The techniques presented work for dynamic constraints and their corresponding transition graphs as well as for simple static constraints. Only passive reactions (rollbacks) to constraint violations are provided by the trigger patterns, but the systematic generation of such patterns should help the database designer in identifying possible active reactions for repairing constraint violations.>

This paper presents a methodology for the stepwise specification of dynamic database behaviour. A conceptual schema is described in three levels: data, objects and transactions. To determine which sequences of database states are “admissible”, integrity constraints on objects are given in temporal logic. Transactions are specified by pre/postconditions to produce “executable” state sequences. In order to guarantee that executable state sequences already become admissible, integrity constraints are completely transformed into additional pre/postconditions. We introduce general rules for these transformations. Thus, schema specifications can be refined and simplified systematically.