PostgreSQL: Introduction and Concepts 
by Bruce Momjian
The most advanced, feature-rich SQL database server available, the open-source PostgreSQL system has rapidly become a key Internet technology. PostgreSQL: Introduction and Concepts, written by a founding member of the PostgreSQL Global Development Team, provides a much-needed tutorial and real-world guide to understanding and working with this complex yet essential system....
Price: $9.23 | Publisher: Addison-Wesley | Release: 2000
by Steven Feuerstein, Charles Dye, John Beresniewicz
Oracle's built-in packages dramatically extend the power of the PL/SQL language, but few developers know how to use them effectively. This book is a complete reference to all of the built-ins, including those new to Oracle8. the enclosed diskette includes an online tool that provides easy access to the many files of source code and documentation developed by the authors....
Price: $4.38 | Publisher: O'Reilly Media | Release: 1998