"By Example" cookbook pages will provide coding examples for many of the commonly used classes within Yii. We will try to provide as many usage examples as possible for keep these pages as helpful as possible.
The customary configuration of a Yii application includes just a single database section in the protected/config/main.php file, but it's easy to extend this to support more than one, tying each Model to one of the databases.
Authentication and Authorization is a good tutorial. Among other topics, it describes basic aspects of Yii's RBAC implementation. But however hard I read the tutorial, I couldn't understand how exactly the hierarchy works. I found how to define authorization hierarchy, how business rules are evaluated, how to configure authManager, but almost nothing about how I should build my hierarchy, in what sequence its nodes are checked, when the checking process stops and what would be the checking result.