edib

To use the most modern version of Postgres software we need to add postgresql repository. Edit /etc/apt/sources.list or create /etc/apt/sources.list.d/pgdg.list and add there a line: deb http://apt.postgresql.org/pub/repos/apt/ jessie-pgdg main Then import the repository signing key, and update the package lists:

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

Install a new version of PostgreSQL server.

Once the Debian upgrade finished, I used dpkg-query -l postgresql* to check which versions of postgres I have installed.

edib

# See https://wiki.postgresql.org/wiki/Using_pg_upgrade_on_Ubuntu/Debian for more information and warning!

# Check first
/usr/lib/postgresql/11/bin/pg_upgrade \
   -b /usr/lib/postgresql/9.6/bin \
   -B /usr/lib/postgresql/11/bin \
   -d /var/lib/postgresql/9.6/main \
   -D /var/lib/postgresql/11/main \
   -o ' -c config_file=/etc/postgresql/9.6/main/postgresql.conf' \
   -O ' -c config_file=/etc/postgresql/11/main/postgresql.conf' \

edib

sudo apt-get install postgresql-9.6 postgresql-server-dev-9.6 postgresql-contrib-9.6 -y
 
sudo su - postgres -c "psql template1 -p 5433 -c 'CREATE EXTENSION IF NOT EXISTS hstore;'"
sudo su - postgres -c "psql template1 -p 5433 -c 'CREATE EXTENSION IF NOT EXISTS \"uuid-ossp\";'"
sudo systemctl stop postgresql
sudo su - postgres -c '/usr/lib/postgresql/9.6/bin/pg_upgrade -b /usr/lib/postgresql/9.3/bin -B /usr/lib/postgresql/9.6/bin \
-d /var/lib/postgresql/9.3/main/ -D /var/lib/postgresql/9.6/main/ \
-O "-c config_file=/etc/postgresql/9.6/main/postgresql.conf" -o "-c config_file=/etc/postgresql/9.3/main/postgresql.conf" --link'
 
sudo apt-get remove postgresql-9.3 -y