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Cheat Sheet for Administrating a PostgreSQL Database/Server

  • byJordan
  • July 16, 2012
  • 1 minute read

PostgreSQL Interactive Terminal

 

Postgresql is similar to MySQL in that it uses an interactive terminal. To gain access type the following as root

su - postgres -c psql

You’re now logged into the Postgresql interactive terminal and interacting with the local server.

Common Shell Commands

 

Dump a database.

When dumping and restoring a database, you have to work within the postgres user, this is the default setup. The home directory for the postgres user is /var/lib/postgresql

pg_dump -U username database -f file.sql

 

Restore a database.

In order to restore the database you will need to ensure that the database name exist, for instance if it was dropped.

psql -U username -d database -f file.sql

 

Common Interactive Terminal Commands

 

Connect to a database, like “use database” in MySQL.

connect databasename;

 

View current databases on local server

select datname from pg_database;

 

View current databases on local server

\l

 

 Show current roles

select rolname from pg_roles;

 

Create a user.

create user ramesh with password 'tmppassword';

 

Create a database.

CREATE DATABASE mydb WITH OWNER ramesh;

 

Drop database.

DROP DATABASE mydb;

If you notice that you’re unable to drop a database because of connections, then run the following.

SELECT
pg_terminate_backend(procpid)
FROM
pg_stat_activity
WHERE -- don't kill my own connection!
procpid <> pg_backend_pid();

If it’s a busy database then you may need to run the following first.

REVOKE CONNECT ON DATABASE dbname FROM PUBLIC, username;