CGridview displays existent rows of the table (using DataProvider)
Suppose we want to set a category to product (or an item in general term), Also suppose categories has sub-categories (multi-level)
There are cases you want to update a record on CGridview directly
Suppose you have an Application in Yii that manages hotels each one has many customers.
Ok, it is a little bit difficult to full understanding the unsafe validator.
Everyone have seen a multilayer menu in several CMS
Relational databases do not support inheritance so if we need to represent it, we have to somehow store meta info while keeping performance by minimizing JOINs. One way to solve this problem is using single table inheritance. All fields for the whole class tree are stored in a single table. Class name is stored in the type field...
This is a reference to be used for Model rule validation and is compiled from the Yii documentation and code. The purpose is to have all the information gathered in one place instead of scattered. This reference is not an intro. See The Definitive Guide to Yii, Declaring Validation Rules for a tutorial.