Relational Database Systems provides a timely introduction to the kinds of systems that are the current mainstay of the database management field. This book serves as a text for advanced undergraduate and graduate students and as an informative reference for researchers and professionals in all database aspects of computer science. It presents important querying systems, including SQL and QUEL, and covers their respective theoretical foundations in relational algebra, tuple calculus, and domain calculus. The book assumes a knowledge of programming languages and datastructures and some mathematical induction.