This book targets the theoretical/conceptual details of high performance parallel database processes, forming a base of understanding and delivering practical information on development, implementations and analytical modeling of parallel databases. It also includes key information on new developments with grid databases. The book explains the practical aspects, including use of Oracle Parallel Query Execution, to show how parallel query is executed in a Database Management System (DBMS). It also presents Java Thread Programming to illustrate and implement parallel algorithms. The book balances the theoretical with the practical to support in-depth study of parallel query processing offered by modern DBMS as well as hands-on experience in the development, implementation, and analysis of parallel query algorithms.