Queries and query processing in object-oriented database systems
David D. Straube, M. TAMER ÖZSU · ACM Transactions on Information Systems · 1990
Object-oriented database mangement systems (OODBMS) combine the data abstraction and computational models of object-oriented programming languages with the query and performance capabilities of database management systems. A concise, formal data model for OODBMS has not been universally accepted, preventing detailed investigation of various system issues such as query processing. We define a data model that captures the essence of classification-based object-oriented systems and formalize concepts such as object identity, inheritence, and methods. The main topic of the paper is the presentation of a query processing methodology complete with an object calculus to object algebra translation are discussed in detail. The paper concludes with a discussion of equivalence-preserving transformation rules for object algebra expressions.