How to connect to a postgres database in a docker container?

Question

I setup my django and postgres container on my local machine and all working fine. Local server is running, database running but I am not being able to connect to the created postgres db.

docker-compose.yml

version: '3'

services:
  web:
    build: .
    command: python manage.py runserver 0.0.0.0:8000
    volumes:
      - .:/app
    ports:
      - "8000:8000"
    depends_on:
      - db

  db:
    image: postgres:13.0-alpine
    volumes:
      - postgres_data:/var/lib/postgresql/data/
    environment:
      - POSTGRES_USER=my_user
      - POSTGRES_PASSWORD=my_password
      - POSTGRES_DB=my_db

volumes:
  postgres_data:

I tried this command: docker exec -it container_id psql -U postgres error: psql: error: could not connect to server: FATAL: role "postgres" does not exist

I am very new to Docker.

Answer 1

You're not using the username and the password you provided in your docker-compose file. Try this and then enter my_password:

docker exec -it container_id psql -U my_user -d my_db --password

Check the official documentation to find out about the PostgreSQL terminal.