Run Postgres in a Docker container using Docker Compose.
While it's pretty easy to install, start, stop, and upgrade Postgres on your Mac using Homebrew, it takes even fewer steps to run it in a Docker container. In your own development workflow you might even prefer to run Postgres in Docker because you likely want to destroy and recreate your database state over and over again during your development and testing cycle. If you are already using Docker to run other services, it's a small incremental cost to also run Postgres in a container. On the other hand, if you don't want to pay for the expensive cost of virtualization (CPU, memory and disk access times), consider running Postgres on your Mac natively.
This project provides a prototypical Docker Compose configuration for running Postgres in a Docker container. Of note
is the use of a Docker bind mount on the local postgres-init/ directory into the container at /docker-entrypoint-initdb.d/.
The Postgres Docker container contains some special logic to execute any .sql files in that directory when the database
starts up. This is a convenient way to initialize the database with a schema and/or data.
Follow these instructions to get up and running with Postgres in a Docker container.
- Pre-requisites: Docker
- I'm using Docker Desktop, but you could use an alternative, like Colima.
- Start a Postgres instance using Docker Compose:
-
docker compose up
- Note: you'll usually want to use the
--detachoption so that the container runs in the background. For this example, we want to take a moment and actually inspect the output of the container startup. What do you notice?
-
- Explore the database! Enter a session on the command line:
-
docker exec --interactive --tty docker-postgres-1 psql --username postgres --host localhost - Try something like
select 1 + 2;orselect region, count(*) from destinations group by region order by region;. - When you are finished, exit the session with
\q.
-
- Stop the Postgres Docker container:
-
docker compose down
-