Model-theoretic minimal change operators for constraint databases

Abstract

Database systems should allow users to insert new information (described by a first-order sentence) into a database without specifying exactly how. The database systems should be able to figure out what tuples to add or delete from the current database to satisfy fully the user's request. The guiding principle of accomplishing such insertions is the concept of model-theoretic minimal change. This paper shows that this concept can be applied to constraint databases. In particular, any constraint database change operator that satisfies the axioms for revision [AGM85], update [KM92], or arbitration [Rev96] accomplishes a model-theoretic minimal change in a well-defined sense. The paper also presents concrete operators for revision, update, and arbitration for constraint databases with real polynomial inequality constraints.