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Dump And Restore A PostgreSQL Database

PostgreSQL comes with two command-line utilities for dumping and then restoring a database — pg_dump and pg_restore, respectively.

Using the pg_dump with the -Fc flag will create a dump of the given database in a custom format. The output of this command can be redirected into a file (the .dump extension is a standard convention):

$ pg_dump -Fc my_database > my_database.dump

Using the custom format option provides a couple benefits. The output is significantly compressed in comparison to a generic SQL dump. The dump and restoration is more flexible. Lastly, the dump can be performed in parallel if your machine has multiple cores to work with. Likewise, the restoration can be done in parallel with multiple jobs.

To restore the dump, create a fresh database and then use pg_restore:

$ createdb my_new_database
$ pg_restore -d my_new_database my_database.dump

Note: the dumped tables will depend on some user role. You will need to ensure that this role exists on the database cluster where the restore is happening. You can use the createuser command if necessary.

See the pg_dump docs and pg_restore docs for more details.

Looking for help? Hashrocket developers believe that data quality is as important as code quality. We enjoy all the challenges of relational databases, from finding the fastest index, to structuring data to fit the needs of an application. We're eager to share our experiences; check out PG Casts, a series of free weekly PostgreSQL screencasts.