Hypothetical Temporal Reasoning in Databases

摘要

In this paper we integrate a history–encoding based methodology for checking dynamic database integrity constraints into a situation-calculus based specification of relational database updates. By doing this, we are able to: (1) Answer queries about a whole hypothetical evolution of a database, without having to update the entire database and keep all the information associated to the generated states, (2) State and prove dynamic integrity constraints as static integrity constraints, (3). Transform history dependent preconditions for updates into local preconditions.