In this tutorial, we will show you how to install PostgreSQL on your Debian 9 server. For those of you who didn’t know, PostgreSQL is a free, open-source object-relational database management system (object-RDBMS), similar to MySQL, and is standards-compliant and extensible. It is commonly used as a back-end for web and mobile applications. PostgreSQL, or ‘Postgres’ as it is nicknamed, adopts the ANSI/ISO SQL standards together, with the revisions.
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 through the step by step installation of PostgreSQL on a Debian 9 (Stretch) server.
Install PostgreSQL on Debian 9 Stretch
Step 1. Before we install any software, it’s important to make sure your system is up to date by running these following apt-get commands in the terminal:
apt-get update apt-get upgrade
Step 2. Installing the PostgreSQL server.
PostgreSQL is available in the default repositories. Now, Install PostgreSQL packages using apt-get:
apt-get install postgresql-9.6
Start the PostgreSQL service also needs to be enabled to start on reboot using the following command:
systemctl start postgresql systemctl enable postgresql
Now we can confirm the installation using some commands. They are given below:
ps -ef | grep postgre
You should see something like this on the terminal:
postgres 32162 1 0 22:58 ? 00:00:00 /usr/lib/postgresql/9.4/bin/postgres -D /var/lib/ postgresql/9.4/main -c config_file=/etc/postgresql/9.4/main/postgresql.conf postgres 32168 32164 0 22:58 ? 00:00:00 postgres: checkpointer process postgres 32167 32164 0 22:58 ? 00:00:00 postgres: writer process postgres 32169 32164 0 22:58 ? 00:00:00 postgres: wal writer process postgres 32160 32164 0 22:58 ? 00:00:00 postgres: autovacuum launcher process postgres 32171 32164 0 22:58 ? 00:00:00 postgres: stats collector process
Step 3. Access PostgreSQL command prompt.
After installing the PostgreSQL database server, by default, it creates a user ‘postgres’ with role ‘postgres’. It also creates a system account with same name ‘postgres’. So to connect to postgres server, login 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:
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:
Create a new user and database:
### For example, let us create a new user called “idroot” with password “idrootus”, and database called “idrootdb”. ### sudo -u postgres createuser -D -A -P idroot sudo -u postgres createdb -O idroot idrootdb
Congratulations! You have successfully installed the PostgreSQL Server. Thanks for using this tutorial for installing PostgreSQL in Debian 9 Stretch systems. For additional help or useful information, we recommend you to check the official PostgreSQL website.