A SURVEY OF QUERY OPTIMIZATION IN CENTRALIZED DATABASE SYSTEMS

Abstract

Efficient ways to process unanticipated queries are a crucial prerequisite for the success of generalized database management systems. A wide variety of approaches for improving the performance of query evaluation algorithms have been proposed: logic-based and semantic transformations, fast implementations of basic operations, and combinatorial or heuristic algorithms for generating and choosing among alternative access plans. This paper surveys these approaches in the framework of a general query evaluation procedure using the relational calculus representation of queries. The focus is on centralized database systems; some relationships to other system types are studied.