Generic update operations keeping object-oriented databases consistent

One of the objectives of ooDBMSs is to use type-specific methods for manipulating objects, in order to maintain the consistency of the database. This is, however, little help for the method implementor as far as the model-inherent constraints are concerned. We propose a set of generic update operations that maintain integrity constraints such as types, class memberships, subtype-, subclass-relationships, and class predicates. The operations can be used for implementing type-specific update methods or directly by applications. We present an approach to consistently define update semantics for an object model including classes, views, and variables that is based on necessary and sufficient predicates akin to defined concepts in KL-ONE style languages