Difference between #5 and #4 of Code style

Where to put what
------------------

Often, when writing widgets or editing Yii code, it is unclear whether or not
the code is following the MVC pattern.

Here are a few suggestions to help detect the most obvious style errors.

### Controller

The controller should contain code for collecting user input, retrieving models
from the database, and rendering views.

In a controller there should never**never** be:

 - HTML code: HTML should be in the view
 - SQL code: If needed, SQL should be in a modelmodel,
encapsulate in methods.
 - Field names: Field names should be in the view

Avoiding embedding field names allows you to change the database easily.


### Views

HTML code should only be in views.

Views should not**not** contain:

- User input (e.g. $_GET and $_POST): Input should be collected in models in the
controllers, never in views.
- SQL: When needed, it is best to create a function in the model

The fewer PHP operations there are in the views, the better it is. Instead of
concatenating  two fields, it is better to write a getter method, so you can
reuse it in other views.

### Models

Models are used for collecting user inputs, and accessing the database.

In models there should not**not** be:

- User input ($_GET, $_POST): You should write a function that will be called in
the controller. 
- HTML: HTML should be in a view


Widgets
------------------

Widgets have a behaviour similar to controllers. If a widget is supposed to
create a lot of HTML, it is better to create a view file for it.