How to Install PostgreSQL on Arch Linux with Pacman (Step-by-Step)

How to Install and Set Up PostgreSQL on Arch Linux

Step 1: Update Your System

sudo pacman -Syu

This command updates your package database and your system.

Step 2: Install PostgreSQL

To install PostgreSQL, use the Pacman package manager:

sudo pacman -S postgresql

This command will install the PostgreSQL server and client on your system.

Step 3: Initialize the Database Cluster

Before using PostgreSQL, you need to set up the database cluster, which is a group of databases managed by a PostgreSQL server.

sudo -iu postgres
initdb --locale $LANG -E UTF8 -D '/var/lib/postgres/data'

--locale $LANG: Sets the language settings for the database.
-E UTF8: Makes sure the database uses UTF-8 encoding.
-D '/var/lib/postgres/data': Chooses where the data will be stored.

Step 4: Start and Enable the PostgreSQL Service

Now, start the PostgreSQL service and enable it to start on boot automatically:

sudo systemctl start postgresql
sudo systemctl enable postgresql

These commands start the PostgreSQL service, so make sure it starts automatically whenever your system boots.

Step 5: Set Up a PostgreSQL User

To manage databases and users, switch to the PostgreSQL user:

sudo -iu postgres

Create a new PostgreSQL user with:

createuser --interactive

You'll be prompted to enter the username and decide whether the new user should be a superuser.

Step 6: Create a Database

With your PostgreSQL user set up, you can now create a database:

createdb your-database-name

Step 7: Access the PostgreSQL Shell

To start working with your databases, access the PostgreSQL command-line interface (CLI) with:

psql

Or, connect directly to a specific database:

psql mydatabase

Step 8: Exit the PostgreSQL Shell

When you're done, you can exit the PostgreSQL shell by typing:

\q

FAQ

Where does PostgreSQL store its data on Arch Linux?

The database cluster lives in /var/lib/postgres/data by default — that's the directory passed to initdb in Step 3. Back up that directory (or use pg_dump) before system upgrades.

How do I start PostgreSQL automatically on boot?

sudo systemctl enable postgresql creates the boot-time symlink, and sudo systemctl start postgresql starts it immediately. Check status with systemctl status postgresql.

Why do I get "could not connect: No such file or directory"?

That error means the server isn't running — psql can't find the Unix socket. Run systemctl start postgresql, and if it fails, make sure you ran initdb first: a fresh install has no data directory until you initialize the cluster.

How is PostgreSQL different on Arch compared to Ubuntu?

The packages and defaults are nearly identical, but Arch's rolling release means PostgreSQL major-version upgrades arrive sooner and require a manual pg_upgrade of your data directory — Arch won't migrate the cluster for you.