Lots of people are asking how to solve it with YII,We think its difficult with YII. But its easy to solve . There is no database triggers needed . we can simply sove it by extending a class(say "RActiveRecord") from CActiveRecord .Then extend all our model classes from that class.
Few days ago i was playing with TCPF plugin to create a PDF files. Since i have checked few available extension and also checked some forum threads but still i dont get my expected result for PDF file.
If you are coming over to Yii 2 from Yii 1.x, you may have already read this useful wiki for creating dependent dropdowns.
You can use a similar approach in Yii 2 to do the same. But if you are looking at a prebuilt solution that helps you manage it easier, read along.