Exploring the Use of Mixed Abstractions in SQL:1999 - A Framework-Based Approach

SQL: 1999 introduced the capability to support object concepts. It is now possible to design an SQL database schema using relational and object models. Each model represents a different abstraction. We use a framework to understand the implications of this change and to explore the use of mixed abstractions in an SQL: 1999 schema. We describe two new kinds of schema. We find that current object-relational mapping strategies differ in terms of the kind of database schema they produce from the same class model.