Schema Evolution publication categorizer

In this paper, we address the problem of supporting more
flexibility on the schema of object-oriented databases. We describe a
general framework based on an object-oriented data model, where three
levels of objects are distinguished
data objects, schema objects,and meta-schema objects. We discuss the prerequisites for applying the query and
update operations of an object algebra uniformly on all three levels. As
a sample application of the framework, we focus on database evolution, that is, realizing incremental changes to the database schema and their
propagation to data instances. We show, how each schema update of a
given taxonomy is realized by direct updating of schema objects, and
how this approach can be used to build a complete tool for database
evolution.