To install PostgreSQL in ubuntu
Add the repo for postgres to the apt repo list:
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" >> /etc/apt/sources.list.d/pgdg.list' sudo wget -q https://www.postgresql.org/media/keys/ACCC4CF8.asc -O - | sudo apt-key add -
To install the postgres database packages:
sudo apt-get update sudo apt-get install postgresql postgresql-contrib