Local PostgreSQL with Docker Compose

This project defines a local PostgreSQL database using Docker Compose. The manifest in docker-compose.yaml starts a single database container and exposes it on the configured host port.

Prerequisites

• Docker Engine installed and running
• Docker Compose v2 (docker compose) available in your shell

1. Configure environment variables

Create or review the .env file in this directory. The values below are already set for a local development database:

POSTGRES_USER=myuser
POSTGRES_PASSWORD=mypassword
POSTGRES_DB=mydatabase
POSTGRES_PORT=5432

If you want to use a different database name, user, or port, update the values in .env before starting the container.

2. Start the database

From this directory, run:

docker compose up -d db

This creates and starts the PostgreSQL container in the background.

3. Verify the database is running

Check the container status:

docker compose ps

You should see the db service as running.

To inspect the database logs:

docker compose logs -f db

4. Connect to the database locally

The database is exposed on your host machine at localhost:<POSTGRES_PORT>. With the default configuration, that is:

psql -h localhost -p 5432 -U myuser -d mydatabase

When prompted, enter the password from .env:

mypassword

5. Stop and remove the database

To stop the container:

docker compose stop db

To stop it and remove the container and its default network:

docker compose down

To remove the database volume as well (delete all local database data):

docker compose down -v

Notes

• The Compose file maps the container's internal PostgreSQL port 5432 to the host port configured by POSTGRES_PORT.
• The database data is stored in the Docker named volume db_data, so it persists across container restarts unless you explicitly remove it with docker compose down -v.