If you are running a PostgreSQL setup, there are basically two major methods to perform backups:
- Logical dumps (extract an 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 do 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. pg_dump is also the oldest method of creating a backup and has been around since the very early days of the project (transaction log shipping was added much later). Every PostgreSQL administrator will get in touch with pg_dump sooner or later so it is important to know how it really works and what it does.
