docker-compose service without a volume

I have a redis service defined like this in the docker-compose.yml file:

redis:
  container_name: redis
  image: redis
  ports:
    - "6379:6379"

As you can see, there’s no volume(s) defined here. Will the redis database persist between calls to docker run / docker-compose run? I can see some data in the database when I use docker run with redis-cli, so I’m curios where it comes from.

Source: StackOverflow