This book is for PostgreSQL application programmers.  It is divided into three parts.
   
    The first part of this book describes the client programming
    interfaces distributed with PostgreSQL.  Each of these chapters
    can be read independently.  Note that there are many other
    programming interfaces for client programs that are distributed
    separately and contain their own documentation.  Readers of the
    first part should be familiar with using SQL commands to
    manipulate and query the database (see the PostgreSQL 7.3 User's Guide) and of
    course with the programming language that the interface uses.
   
    The second part of this book is about extending the server
    functionality with user-defined functions, data types, triggers,
    etc.  These are advanced topics which should probably be
    approached only after all the other user documentation about
    PostgreSQL has been understood.
   
    The third part of this book described the available server-side
    programming languages.  This information is related to the second
    part and is only useful to readers that have read at least the
    first few chapters thereof.
   
    This book covers PostgreSQL 7.3
    only.  For information on other versions, please read the
    documentation that accompanies that release.