Deriving consistency-preserving transaction specifications for (view-)updates in relational databases

Abstract

We propase a new method for generating transaction specifications for (view-)updates in relational databases that are guaranteed to preserve integrity constraints. The method augments the relational database with a set of transition and events rnles, which explicitly define the insertions and deletions induced by a database update. At database design time, an extension of the SLDNF procedure can use these rules as input clauses to produce transaction specifications for compile-time base or view updates. This is done in such a way that the database will never be taken into an inconsistent state, if run-time updates are only effected through tlw instantiation of the previously obtained transaction specifications. The method draws from previous work of our group in the more general setting of deductive databases, particularly in view updating and integrity constraint checking.