A model for deferred view maintenance

Presents a model for deferred maintenance of object-oriented views. Queries that define views are implemented as methods that are invoked to compute the corresponding views. A deferred update reflects to a view only those related modifications that were introduced into the database while that view was inactive. A view is updated by considering modifications performed within all classes along the inheritance and class-composition subhierarchies rooted at every class used in deriving that view. To each class, we add a modification list to keep one modification tuple per view dependent on that class. Such a tuple acts as a reference point that marks the start of the next update to the corresponding view