The book begins with a thorough overview of SQL, a description of all PostgreSQL data types, and a complete explanation of PostgreSQL commands. If you're a developer or administrator, you'll love the chapter that explores PostgreSQL performance. The authors explain how PostgreSQL stores data on disk (and memory) and how to measure and influence the effectiveness of PostgreSQL's caching mechanisms. The authors describe all the query operators that can appear in the EXPLAIN command, describing the performance implications of each operator and the conditions which will cause PostgreSQL to use that operator. PostgreSQL is also a complete guide for developers. The authors have even included a chapter that walks you through the process of extending the PostgreSQL server with custom functions written in C and new data types.You will learn how to install PostgreSQL on Windows, Linux, and Unix systems, from source code or from pre-compiled installers. The chapter on PostgreSQL security describes all authentication protocols that you can choose from and describes how to secure your database, both internally and externally. If you must support multi-national environment, you will find the chapter on internationalization and localization to be invaluable. You will not find a more complete guide to PostgreSQL anywhere.