A Generic Approach to Schema Evolution in Live Relational Databases

Schema evolution is an important theme for many database users across a broad range of fields. This paper introduces a generic data management layer, GeneRelDB, which allows the schema of a relational database to evolve during run time without the need to rewrite database queries in the application code. It is designed to run as an abstraction layer, handling all communication (queries and data exchange) between the user interface and the database backend. The only restriction to the changes that can be made relate to data type conversion for existing columns in the database. Foreign key constraints are supported and referential integrity is maintained during evolution.