Object-oriented databases intend to support non-traditional database application areas such as artificial intelligence (AI), computer-aided design (CAD), and office information systems (OIS). An important requirement of non-traditional database applications is the support of application evolution which includes evolution of schemas as well as objects. The overall goal of this research is to understand properties of dynamically evolving objects and their schemas and find mechanisms for supporting them in object-oriented databases. One goal of this research is to implement an extensive schema manager having many useful capabilities for dynamic schema management, such as schema evolution, graphics schema editor, schema versioning, DAG rearrangement views, and logical database schema design. Also, in this research, two more issues which are closely related with dynamic schema management will be investigated: (1) storage model issue (i.e., ways of storing dynamic object instances), (2) the issue of how to achieve code (i.e., method) compatibility in the face of dynamic schema changes. This research contributes toward: (1) identifying data structures and operations which are necessary to support dynamic schemas and objects, (2) analyzing basic properties of storage models, and (3) investigating techniques for method conversion which can cope with dynamic schema changes, in object-oriented databases.
