Working with scenarios, with models that can receive many modifications in their rules or structures as development evolves, can create disruptions in the rescue process.
The Problem: Yii2 utilizes by default UserIdentity configured in config/web.php for connection, this object appy one table to authentication ('identityClass' => 'app\painel\models\User'). How to authentication from diferent tables? Solution: Create instances in web.php to uses UserIdentify. eg:
bad design of Active Record.
Uploading files in a webapp can be extremely tricky and sometimes the quickest way to do it is to store the file directly in the webserver or into a DNS (like Amazon S3) and then to save the link and the metadata inside a table in the DB. The thing is that you'll have to deal with file permissions, server storage, file management and so on (which is perfectly fine, by the way).