Resumen de A schema modification methodology for an objet-oriented database system
Proper and efficient handling of schema changes is an important aspect of any object-oriented database management system. This paper deals with the definition of a schema modification methodology for ODS; an object-oriented database management system prototype designed at Bilken University. A brief description of the basic features of ODS is included to facilitate the treatment. The invariants of the class lattice as well as the rules for resolving ambiguities due to schema changes are identified. In addition, schema changes handled by ODS are described within the realm of the specified invariants and rules. The described methodology efficiently handles deletions which are unmanagable in object-oriented systems due to the unidirectional relationship between objects in different classes.
