A Query Algebra for an Extended Object-Oriented Database Model
George D. Loizou, Philippos Pouyioutas · Database Systems for Advanced Applications · 1991
In this paper we extend the objecf-oriented dalabase model via the concept of object inheritance. We then define a closed and safe object-oriented query algebra. Our algebra is different from any other object-oriented query algebra found in the literature due to the extension of the model with object inheritance. The algebra defined deals with homogeneous sets of objects, and provides the model with efficient storage of persistent results of queries involving the project and join operators.