db:
    image: mysql
    environment:
        - MYSQL_ROOT_PASSWORD=root
        - MYSQL_DATABASE=texas_choropleth
web:
    build: .
    command: python src/manage.py runserver 0.0.0.0:8000 --settings=texas_choropleth.settings.local
    volumes:
        - .:/app/
    ports:
        - "8000:8000"
    links:
        - db

db:
    image: mysql:latest
    environment:
        - MYSQL_ROOT_PASSWORD=root
        - MYSQL_DATABASE=texas_choropleth
web:
    build: .
    command: python src/manage.py runserver 0.0.0.0:8000 --settings=texas_choropleth.settings.local
    volumes:
        - .:/app/
    ports:
        - "8000:8000"
    links:
        - db

Use the latest mysql image.
Use the latest mysql image.