How to Install PostgreSQL 9.6 on Ubuntu ?

PostgreSQL is a powerful, open source object-relational database system. It has more than 16 years of active development and a proven architecture that has earned it a strong reputation for reliability, data integrity, and correctness.
 
I am going to share few steps to install PostgreSQL 9.6 on Ubuntu 16.04.

First, check the version of Ubuntu:
lsb_release -sc

You need to add the latest PostgreSQL repository for the latest version, otherwise It will install old version. This is for trusty version.
sudo add-apt-repository "deb https://apt.postgresql.org/pub/repos/apt/ trusty-pgdg main"

Update and Install PostgreSQL 9.6:
sudo apt-get update
sudo apt-get install postgresql-9.6

Default postgres super user and postgres database is created. You need to set a password for the postgres super user. 
ubuntu@:~$ sudo passwd postgres
Enter new UNIX password:****
Retype new UNIX password:****
passwd: password updated successfully

If service is not started, you can start the PostgreSQL service. 
sudo service postgresql start

Connect PostgreSQL server using postgres user:
ubuntu@:~$ su postgres
Password:****

Create a sample database:
createdb database_name

Connect to that database:
psql -d database_name

Create a sample table:
create table Test (rno integer);

Exit to database session:
\q

Exit to PostgreSQL server:
exit