Post-installation
After PostgreSQL is installed and the postgres user has been created, there are a few steps left before you can connect to the database server.
Create the data directory
Create a data directory and change its user and group ownership to postgres:
% sudo mkdir /usr/local/pgsql/data
% sudo chown postgres:postgres /usr/local/pgsql/data
Initialize the data directory
Run initdb as the postgres user to initialize the data directory:
% sudo -u postgres /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
Start the server
Run pg_ctl as the postgres user to start the server, specifying the location of the data directory and the log. (Backslashes “\” are used to continue a command to the next line.)
% sudo -u postgres /usr/local/pgsql/bin/pg_ctl \
-D /usr/local/pgsql/data \
-l /usr/local/pgsql/data/logfile start
Hopefully, you’ll see this message:
waiting for server to start.... done
server started
To stop the server:
% sudo -u postgres /usr/local/pgsql/bin/pg_ctl \
-D /usr/local/pgsql/data stop
Configure Your Shell
In order to launch programs like psql without typing the full path (/usr/local/pgsql/bin/psql), add the PostgreSQL bin directory to your shell’s environment variable by adding these lines to your shell’s startup file:
PATH="/usr/local/pgsql/bin:$PATH"
export PATH
If you installed the documentation, also add these lines so you can view them with the man command:
MANPATH=/usr/local/pgsql/share/man:$MANPATH
export MANPATH
Connect to the server
The default settings allow the postgres superuser to connect to a server running on the same computer without a password.
Connect to the server as the postgres user:
% psql -U postgres
If everything worked, you should be connect to a database (also named “postgres”) and see something like this:
psql (14.1)
Type "help" for help.
postgres=#
My local installation of PostgreSQL is used for learning, development and testing. It does not contain any private or sensitive information, so I leave the password blank for convenience.
If you need to set a password, use the ALTER USER command:
postgres=# ALTER USER postgres PASSWORD 'myPassword';
ALTER ROLE