This book describes the standard Java interfaces that make portable object-oriented access to relational databases possible and offers a robust model for writing applications that are easy to maintain. It introduces the JDBC and RMI packages and uses them to develop three-tier applications (applications divided into a user interface, an object-oriented logic component, and an information store). The book begins with a quick overview of SQL for developers who may be asked to handle a database for the first time. It then explains how to issue database queries and updates through SQL and JDBC. It also covers the use of stored procedures and other measures to improve efficiency, where these are available. But the book's key contribution is a set of patterns that let developers isolate critical tasks like object creation, information storage and retrieval, and the committing or aborting of transactions. The second edition includes more basics of JDBC and SQL, with more examples, and a deeper discussion about the architecture of a robust, maintainable database application. The second edition also explains the relationship between JDBC and Enterprise JavaBeans.