In this exercise, we'll go thru our steps for upgrading a Redhat Enterprise Linux 64-bit PostgreSQL
box from PostgreSQL 8.3 to PostgreSQL 8.4. If you don't have any kind of PostgreSQL installed on your box,
you can skip the Upgrade step.
UPDATE - since Devrim's move from Command prompt - he has started a new yum repository. You may want to use
this one instead since it seems more up to date than the other. http://yum.pgrpms.org/
If you are starting from scratch -- just skip this section.
If you are upgrading from 8.4.0 to 8.4.1 you can get away with a simple yum update postgresql and skip the rest of this article.
If you are upgrading from PostgreSQL 8.3 to 8.4, in theory you can use PgMigrator, but in practice,
particularly with a Yum install, you are bound to run into obstacles. If you are running an older version, you must dump and restore.