Stepwise specification of dynamic database behaviour

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.