Schema Evolution publication categorizer

Database schema evolution refers to changes of a database schema that occur during the lifetime of the corresponding database. It particularly refers to changes of schema elements already stored in the database.
In this paper, we give an overview of schema evolution operations supported by the SQL-99 standard. We also compare major commercial (object-)relational database management systems with respect to the support
of these operations and others disregarded in SQL-99. Finally, we conclude with some remarks on open schema evolution issues neglected in SQL-99 as well as in the current implementations of commercial database management
systems.