MotivationThe main idea behind any type of database replication is to be able to tell your database to report to someone (usually to another database) via any of the mechanisms described below whenever changes to your main database have been made. Those changes will then be processed and applied to this second database, and if everything goes well, you will end up having an up to date replica of your main database running somewhere else. This can be useful for many reasons.
Slony-I is a popular PostgreSQL replication system. Basically, it allows you to automatically copy data from one database to other databases. It can also do a couple of other things, but in this article we will concentrate on replication and provide you with a step by step guide on how to configure your first Slony-I cluster in Windows. It will involve a master node and two slave nodes. The master node will be the database that will be replicated and the slaves will get updated as the master gets modified.