Installing PSQL on PopOs!:

sudo apt-get update
sudo apt-get install apt-utils
sudo apt-get install -y postgresql postgresql-contrib

psql --verison

sudo service postgresql # status for checking the status of your database.
sudo service postgresql # start to start running your database.
sudo service postgresql stop # stop running a db

sudo service postgresql start

sudo service postgresql start
sudo -u postgres psql

# uninstall
apt-get purge postgresql*
sudo apt-get autoremove
# List all PG related packages
dpkg -l | grep postgres
# Remove Folders
sudo rm -rf /var/lib/postgresql/
sudo rm -rf /var/log/postgresql/
sudo rm -rf /etc/postgresql/

# Switch over to the postgres account on your server
sudo -i -u postgres
# Accessing a Postgres Prompt Without Switching Accounts
sudo -u postgres psql