Schema Evolution publication categorizer

Features specially devoted to schema evolution in the F2 object-oriented
database system are presented in this paper. They include
a meta-circular and reflective model where primitive operations
(create, update, delete) on schema objects form a complete
taxonomy of schema changes. All the schema objects of a database
are updatable and the consequences of these changes on objects
are handled either by the trigger mechanism or by the
automatic enforcement of the model invariants. The non-traditional