PostgreSQL

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Revision as of 21:25, 29 November 2017 by imported>Samueldr (Adds citation/source for ident authentication use.)

Using psql

Depending on the system.stateVersion of your system, the default super-user username will change:

  • 17.03 and earlier: the superuser is root
  • 17.09 and later: the superuser is postgres

There is no password, Ident Authentication is used. This means that you can access the database using a system user named like the database user.

Example for a 17.03 stateVersion.

 $ sudo -u root psql
psql: FATAL:  database "root" does not exist
 $ sudo -u root psql -l
                              List of databases
   Name    | Owner | Encoding |   Collate   |    Ctype    | Access privileges
-----------+-------+----------+-------------+-------------+-------------------
 postgres  | root  | UTF8     | en_CA.UTF-8 | en_CA.UTF-8 |
 template0 | root  | UTF8     | en_CA.UTF-8 | en_CA.UTF-8 | =c/root          +
           |       |          |             |             | root=CTc/root
 template1 | root  | UTF8     | en_CA.UTF-8 | en_CA.UTF-8 | =c/root          +
           |       |          |             |             | root=CTc/root
(4 rows)

The first error is not an error with the credentials, but an error coming from the default behaviour of psql that is trying to use a database name named like the user logging-in. The second command lists tables available.