authelia/docs/configuration/storage/mysql.md

layout	title	parent	grand_parent	nav_order
default	MySQL	Storage backends	Configuration	2

MySQL

storage:
  mysql:
    host: 127.0.0.1
    port: 3306
    database: authelia
    username: authelia
    # Password can also be set using a secret: https://docs.authelia.com/configuration/secrets.html
    password: mypassword

Loading a password from a secret instead of inside the configuration

Password can also be defined using a secret.