Formalizing Database Evolution in the Situation Calculus

We continue our exploration of a theory of database updates (Reiter [21, 23]) based upon the situation calculus. The basic idea is to take seriously the fact that databases evolve in time, so that updatable relations should be endowed with an explicit state argument representing the current database state. Database transactions are treated as functions whose effect is to map the current database state into a successor state. The formalism is identical to that arising in the artificial intelligence planning literature and indeed, borrows shamelessly from those ideas. Within this setting, we consider several topics, specifically: 1. A logic programming implementation of query evaluation. 2. The treatment of database views. 3. State constraints and the ramification problem. 4. The evaluation of historical queries. 5. An approach to indeterminate transactions. 1 Introduction Elsewhere (Reiter [21, 23]), we have described how one may represent databases and their update transactions with..