Multiple Docker Compose configurations on a single machine

Create a network with Docker this will be permanent and can be reused by docker-composes.

docker network create local-shared-network

In this example we have 2 docker-compose:

First one is to describe our database:

version: "3"

services:
  mysql:
    image: mysql:9
    container_name: mysql_container
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: your_root_password
      MYSQL_DATABASE: your_database_name
      MYSQL_USER: your_user_name
      MYSQL_PASSWORD: your_user_password
    volumes:
      - ./mysql_data:/var/lib/mysql
    ports:
      - "3306:3306"
    networks: 
      - local-shared-network 

networks: 
  local-shared-network: 
    external: true 

Second one is for describe our Application:

version: "3"

services:
  phpmyadmin:
    image: phpmyadmin
    restart: always
    ports:
      - "8090:80"
    environment:
      PMA_HOST: mysql_container
      MYSQL_ROOT_PASSWORD: your_root_password
    networks:
      - local-shared-network

networks: 
  local-shared-network: 
    external: true 

As it in the example above the PHPMyadmin service can access the Database with using, even they are created in different compose project:

# The reference used to point the MySQL container
PMA_HOST: mysql_container # automatically resolved by Docker to 172.0.0.X IP address, thanks to the local-shared-network