An introduction to schema versioning in OODBMS

Object oriented database management systems (OODBMS) have enormous advantages in comparison to relational systems in modeling highly complex and dynamic application scenarios. Still they lack some flexibility which could help their promotion into widely spread industrial use. Especially engineering environments frequently require schema changes to handle evolving designs. The main contribution of the paper is twofold: firstly, we give an overview of schema evolution mechanisms, describing the state of the art in research. To the best of our knowledge, no such comprehensive overview has been published so far. Secondly, the study of a general application scenario led us to a list of requirements. We propose a general framework based on schema versioning to meet those requirements.