How To Install PostgreSQL on Ubuntu 20.04 LTS

In this tutorial, we will show you how to install PostgreSQL on Ubuntu 20.04 LTS. For those of you who didn’t know, PostgreSQL is a relational database management system that provides an implementation of the SQL querying language. It’s standards-compliant and has many advanced features like reliable transactions and concurrency without read locks.

This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of PostgreSQL on a Ubuntu 20.04 (Focal Fossa) server. You can follow the same instructions for Ubuntu 18.04, 16.04, and any other Debian-based distribution like Linux Mint.

Prerequisites

• A server running one of the following operating systems: Ubuntu 20.04, 18.04, 16.04, and any other Debian-based distribution like Linux Mint.
• It’s recommended that you use a fresh OS install to prevent any potential issues.
• SSH access to the server (or just open Terminal if you’re on a desktop).
• A non-root sudo useror access to the root user. We recommend acting as a non-root sudo user, however, as you can harm your system if you’re not careful when acting as the root.

Install PostgreSQL on Ubuntu 20.04 LTS Focal Fossa

Step 1. First, make sure that all your system packages are up-to-date by running the following apt commands in the terminal.

sudo apt update
sudo apt upgrade

Step 2. Installing PostgreSQL on Ubuntu 20.04.

Install the PostgreSQL package using the apt command:

sudo apt install postgresql postgresql-client

By default, the PostgreSQL service is started automatically after the installation. You can confirm if it is running with the command:

systemctl status postgresql.service

Step 3. Configure PostgreSQL.

We need to configure PostgreSQL to listen on all adaptors or system IP addresses to allow applications hosted on external machines to connect to the database:

sudo nano /etc/postgresql/12/main/postgresql.conf

Then, set the listen_addresses to * or (Ip_Address):

listen_addresses = '*'

Restart the PostgreSQL service:

sudo systemctl restart postgresql

Step 4. Accessing the PostgreSQL command prompt.

Once installing the PostgreSQL database server, by default, it creates a user ‘postgres’ with role ‘postgres’. It also creates a system account with the same name ‘postgres’. So to connect to the Postgres server, log in to your system as user Postgres and connect database:

su - postgres
psql

Now you are logged in to the PostgreSQL database server. To check login info use the following command from the database command prompt:

postgres-# \conninfo

To disconnect from the PostgreSQL database command prompt just type the below command and press enter. It will return you back to the Ubuntu command prompt:

postgres-# \q

Create a new user and database:

### For example, let us create a new user called “meilana” with password “maria”, and database called “meilanadb”. ###
sudo -u postgres createuser -D -A -P meilana
sudo -u postgres createdb -O meilana meilanadb

Congratulations! You have successfully installed the PostgreSQL Server. Thanks for using this tutorial for installing PostgreSQL in Ubuntu 20.04 LTS (Focal Fossa) systems. For additional help or useful information, we recommend you check the official PostgreSQL website.