How to install Post­greSQL on Ubuntu

The database man­age­ment system (DBMS) Post­greSQL can be installed on Ubuntu 20.04 with just a few commands. Use this step-by-step guide, which takes you from in­stal­la­tion all the way through to creating a database.

Re­quire­ments for an Ubuntu server with Post­greSQL

A simple database server with Post­greSQL doesn’t need a lot of computing power. Even a simple con­fig­u­ra­tion will work well:

• 1 GHz CPU
• 2 GB
• 2 GB memory

Depending on the type of data you want to save, you may need to expand your hard drive space.

Install Post­greSQL on Ubuntu

You can install Post­greSQL on Ubuntu 20.04 with just a few commands. To do that, you can use the Linux dis­tri­b­u­tion terminal. You can open the console either from the program overview or the search field. Or you can simply use the keyboard shortcut [Ctrl] + [Alt] + [T].

Step 1: Download and install Post­greSQL

As always, before you install Linux software you need to update the package manager. This ensures that the latest in­stal­la­tion package is used.

sudo apt update
sudo apt upgrade

Enter this simple command to download and install the Post­greSQL package.

sudo apt install postgresql

You now just need to confirm it. This will then install the DBMS.

Step 2: Activate Post­greSQL

Once you’ve installed the DBMS, you can start Post­greSQL:

sudo systemctl start postgresql

To find out whether Post­greSQL is working properly, you can check its status:

sudo systemctl status postgresql

You should see that that service is “active”. To quit the status display, press the [Q] key.

Step 3: Use Post­greSQL

Once installed, you’ll find a generic account in Post­greSQL called “postgres”. You can activate it by using the following command:

sudo -i -u postgres

Ubuntu will now act as if you were connected to the Post­greSQL account. From here you will be able to access the DBMS’ input prompt.

psql

This part requires you to work with Post­greSQL. To display which con­nec­tion is currently active, you can use the following command:

\conninfo

To leave the area you can use the following command:

\q

Step 4: Create databases

Alongside the role “postgres” the system has au­to­mat­i­cal­ly created a cor­re­spond­ing database. Your Post­greSQL server can, however, work with multiple databases at the same time. You can create a new database by using the following command, you can choose another name instead of “example”:

CREATE DATABASE example;

Make sure you don’t forget the semicolon at the end when using this command.

To display which database you’ve created, you can use the following command:

\list

The short form “\l” (small L) will also work.

Close

If you want to work directly in a database, you can simply select it. The active database will be displayed in the input row of the Post­greSQL console. To change the database, you can enter the following command and enter the name of the database you want to use:

\c example

Close

To delete a database, you can use the following code:

DROP DATABASE example;

But be careful because you can’t go back if you change your mind. Use this command only when you have to and carefully consider if you really want to delete the database.