In order for this book to be useful, you need at least access to a PostgreSQL client that is allowed to execute queries on a server. Ideally, you'll also be the server administrator. Full client and server packages for PostgreSQL are available for most popular operating systems at http://www.postgresql.org/download/.
All of the examples here are executed at a command prompt, usually running the
psql program. This makes them applicable to most platforms. It's straightforward to do many of these operations instead using a GUI tool for PostgreSQL, such as the pgAdmin III program.
There are some scripts provided that are written in the bash scripting language. If you're on Windows, the cygwin software suite available from ...