# If you run the container with a command like the following:
# sudo docker run --name some-mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql:tag

sudo docker exec -t -i some-mysql /bin/bash
mysql -uroot -pmy-secret-pw

# An example below:
sudo docker run --name mysqldb -e MYSQL_ROOT_PASSWORD=MySecretPass -d mysql:latest
sudo docker start mysqldb
sudo docker exec -t -i mysqldb /bin/bash
mysql -uroot -pMySecretPass