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.
Many Yii users ask how to create helper classes and functions, and though there are numerous approaches spread out among the forum and wiki articles, this Tutorial tries to bring it all together in one place.
Occasionally one wishes to set systemwide parameters for an application, such as a contact address for email, an application name, or setting an option that guides major behavior. Yii provides for setting of static parameters in the configuration file, and this article talks about how to do it conveniently.
This wiki is a step-by-step example explaining how the controller, model and the view's CGridView work together. It explains simple things - as well as more complex things that you will anyway quickly have to know. So, even if you don't use dynamic gridviews, take a morning off and thoroughly work through this tutorial. It should save you lots of struggling.
To fix issues with display of special language characters once and for all
there's a solution: use Unicode UTF-8 everywhere. If everything is set up to use Unicode, you can use mostly every language in your application.
Trying to learn and help some other programmers to find their solutions on the Yii Forum (I think is a superb way to learn the framework), I was facing one challenge with an external library that a fellow programmer wanted to use -quite good indeed: PHPExcel. And what is PHPExcel?