The application that we are going to develop has a very simple architecture. We are going to use Ext JS 5 on the frontend, which is going to communicate with a server-side module using Ajax/JSON, which will then communicate with a database.

The following diagram encapsulates the preceding paragraph:

The server-side module will be developed using PHP. You need not worry if you don't know PHP. We are going to use very basic code (no frameworks), and we are going to focus on the programming logic that needs to be implemented on the server side. This way, you can apply the same logic using any other programming language, such as Java, ASP.NET, Ruby, Python, or any other (that supports the exchange of data in JSON or XML format as this is the communication format used by Ext JS). For the database, we will use MySQL. We will also use the Sakila sample schema (http://dev.mysql.com/doc/sakila/en/), a free MySQL sample database, which is perfect to demonstrate...