Implementing Lazy Database Updates for an Object Database System

Abstract Current object database management systems support user-defined conversion functions to update the database once the schema has been modified. Two main strategies are possible when implementing such database conversion functions: immediate or lazy database updates. In this paper, we concentrate our attention to the definition of implementation strategies for conversion functions implemented as lazy database updates. 1 Introduction Schema evolution in an object database system (ODBS) refers to the ability to change both the schema and consequently the database. Every time a schema is modified then the database has to be updated to be brought up to a consistent state with respect to the new schema. Some commercial ODBSs on the market allow both updating the schema and the database.