Suppose you’re using Docker Compose and you’ve configured Postgres to run as one of your services. Perhaps with a docker-compose.yml file like this:

version: '3'

services:
  database:
    image: postgres:${POSTGRES_VERSION:-13}-alpine
    ports:
      - "5432"
    environment:
      POSTGRES_DB: ${POSTGRES_DB:-app}
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-ChangeMe}
      POSTGRES_USER: ${POSTGRES_USER:-symfony}
    volumes:
      - db-data:/var/lib/postgresql/data:rw

volumes:
  db-data:

Suppose you’ve started your services using docker-compose up -d, ran docker-compose ps and see the following containers:

NAME                    COMMAND                  SERVICE             STATUS              PORTS
guestbook-database-1    "docker-entrypoint.s…"   database            running             0.0.0.0:51961->5432/tcp

You should be able to connect to this Postgres database with the following TablePlus connection settings: