PostgreSQL Administration

PostgreSQL administration is the work around the database, not the SQL inside an application. You run the server, decide who may connect, keep storage healthy, observe what it is doing, and make failure recoverable. A query can be correct while the server that runs it is unavailable, full, or impossible to restore. Administration owns those conditions.

PostgreSQL calls one running server instance a database cluster. A cluster contains one or more databases, plus shared configuration and system catalogs. The postgres server process owns that cluster. Client programs such as psql, pg_dump, and pg_basebackup connect to it over the PostgreSQL protocol.

The operating layers

Most administration work fits one of seven layers. Identify the layer before changing anything. It tells you which configuration, command, or view is relevant.

Configuration and connection policy

postgresql.conf holds server settings. It controls items such as memory, logging, network listeners, and write-ahead log behavior. PostgreSQL can also read settings from included files, which lets you separate local values from configuration managed by your deployment system.