Model-Theoretic Minimal Chenge Operators for Constraint Databases

Database systems should allow users to insert new information (described by a rst-order sentence) into a database without specifying exactly how. The database systems should be able to gure 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 satisses the axioms for revision AGM85], update KM92], or arbitration Rev96] accomplishes a model-theoretic minimal change in a well-deened sense. The paper also presents concrete operators for revision, update, and arbitration for constraint databases with real polynomial inequality constraints.