Upgrade Ubuntu 16.04 postgres from 9 to 12

Linux Postgres Database Ubuntu

Add the repo:

sudo echo 'deb http://apt.postgresql.org/pub/repos/apt/ xenial-pgdg main' > /etc/apt/sources.list.d/pgdg.list

Import the key:

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc |   sudo apt-key add -

Update:

sudo apt update

Install:

sudo apt install postgresql-12 postgresql-client-12 postgresql-contrib-12

Stop:

sudo pg_dropcluster 12 main --stop

Migrate:

sudo pg_upgradecluster 9.5 main

Remove:

sudo pg_dropcluster 9.5 main

Check:

sudo systemctl status postgresql

Double check:

pg_dump -V

From: https://gist.github.com/Clark-G/01fcb84c658c44dcec4af1a965e2c3b4