Query optimization in object-oriented databases

The use of data abstraction in object-oriented databases places a burden on the ability of the system to perform query optimization. A framework for query specification and optimization is discussed that is applicable to object-oriented database systems that take a strict view of data abstraction. Techniques that preserve much of the optimization potential of relational languages by limiting the query language are examined. Techniques are given for query optimization that involve type-specific rewrite rules.<<ETX>>