Application Process Example

A shopping cart application is a good example of when you might use an application process. For example, suppose you need to display the contents of a user's shopping cart with each page view. To accomplish this, you create a region on page zero of your application that displays the values of the application-level items TOTAL_CART_ITEMS and TOTAL_PURCHASE_PRICE.

Instead of writing a process for each page to set the values of TOTAL_CART_ITEMS and TOTAL_PURCHASE_PRICE, you could write an application process of type On Load: Before Header to compute these values. Then, the Application Express engine would execute the process on each page as it renders the application. As a result, each page, would display the most current values for TOTAL_CART_ITEMS and TOTAL_PURCHASE_PRICE.