I have a postgres database on my localhost I can access without a password

$ psql -d mwt
psql (8.4.12)
Type "help" for help.mwt=# SELECT * from vatid;id   | requester_vatid |...-----+-----------------|...   1719 | IT00766780266   |...

I want to access that database from django. So I put in DATABASES

DATABASES = {'default': {'ENGINE': 'django.db.backends.postgresql_psycopg2','NAME': 'mwt','USER': 'shaoran','HOST': 'localhost'}
}

Since I don't need a password to access my test database I didn't provide any PASSWORD value in the settings.

$ ./manage.py shell
>>> from polls.models import Vatid
>>> Vatid.objects.all()connection_factory=connection_factory, async=async)OperationalError: fe_sendauth: no password supplied

I tried using PASSWORD: '' but I get the same error message. I tried to use PASSWORD: None but that didn't help either.

I've been searching the django documentation about this but I cannot find anything useful. It is possible to configure django.db.backends.postgresql_psycopg2 to accept empty password?

Surprisingly, the answer is to not specify a host at all. If you do this,

DATABASES = {'default': {'ENGINE': 'django.db.backends.postgresql_psycopg2','NAME': 'mwt',}
}

Then psycopg2 will connect using a Unix socket in the same manner as psql. When you specify a HOST, psycopg2 will connect with TCP/IP, which requires a password.