How to change PostgreSQL user password?

To log in without a password:

sudo -u user_name psql db_name

To reset the password if you have forgotten:

ALTER USER user_name WITH PASSWORD 'new_password';

To change the the postgres user's password follow this steps

1. Login into the psql:

$ sudo -u postgres psql

2. Then in the psql console change the password and quit:

postgres=# \password postgres
Enter new password: <new-password>
postgres=# \q

or using a query

ALTER USER postgres PASSWORD '<new-password>';

or in one line

sudo -u postgres psql -c "ALTER USER postgres PASSWORD '<new-password>';"

Note:

If that does not work, reconfigure authentication by editing /etc/postgresql/9.1/main/pg_hba.conf (path will differ) and change:

local   all         all                  peer # change this to md5

## to

local   all         all                  md5 # like this

Then restart the server:

$ sudo service postgresql restart