If you are running a PostgreSQL setup, there are basically two major methods to perform backups:
- Logical dumps (extract a SQL script representing your data)
- Transaction log shipping
The idea behind transaction log shipping is to archive binary changes made to the database. Most people claim that transaction log shipping is the only real way to create backups. However, in my opinion, this is not necessarily true.
Many people rely on pg_dump to simply extract a textual representation of the data. Interestingly, pg_dump is also the oldest method of creating a backup and has been around since the very early days of the PostgreSQL project (transaction log shipping was added much later). Every PostgreSQL administrator will become familiar with pg_dump sooner or later, so it is important to know how it really works and what it does.