PostgreSQL Installation and Setup

When installing PostgreSQL a root user named postgresql will be created. But you, not being that user, how can you access the database? How can you use it as a client user?

Some simple steps (client username will be un):^via

As root (use su to change to root if you are not), change to postgresql user:
su - postgres

Connect to pqsql and to the template1 database:
psql template1

Create the user role:
CREATE USER tom WITH PASSWORD 'myPassword';

Create a database:
CREATE DATABASE testdb;

Grant privileges:
>GRANT ALL PRIVILEGES ON DATABASE jerry TO tom;

Done.
\q

Test with:
psql -d un -U tom