Algebraic foundation and optimization for object based query languages

The Tarski algebra, an algebraic foundation for object-based query languages, is presented. While maintaining physical data independence, the Tarski algebra is shown to be both simple and powerful enough to express all reasonable queries. It is shown how queries expressed in a graph-oriented query language (based on the functional data model) can be translated into the Tarski algebra. The graphical representation of queries in combination with the Tarski algebra is shown to be a convenient mechanism for effective query optimization