MYSQL docker user permission & MYSQL need 3306

 For example, if you set:

MYSQL_DATABASE=mydb

MYSQL_USER=myuser

MYSQL_PASSWORD=mypassword

The myuser will have full privileges (such as SELECT, INSERT, UPDATE, DELETE, etc.) on mydb but will not have privileges on other databases unless explicitly granted later.

MYSQL need port 3306, you can map different port from 0.0.0.0 to 3306

You will need a ini file to grant global permission to docker mysql user if you want to 

GRANT ALL PRIVILEGES ON *.* TO 'myuser'@'%'; FLUSH PRIVILEGES;