Managing change in the Rufus system

Abstract

Rufus is an information system that models user data with objects taken from a class system. Due to the importance of coping with changes to the schema, Rufus has adopted the conformity-based model of Melampus [12]. This model enables Rufus to cope with schema changes more easily than traditional class- and inheritance-based data models. This paper reviews the Melampus data model and describes how we implemented it in the Rufus system. We show how changes to the schema can be accommodated with minimum disruption. We also review design decisions that contributed to streamlined schema evolution and compare our approach with those proposed in the literature.