Chapter 8. APEX Validations

APEX validations are part of the Page Processing phase and are fired right after the Computations stage. This is an APEX-declarative, server-side mechanism designed to check and validate the quality, accuracy, and consistency of the page submitted data, prior to saving it into the database. In the case of validation errors, we can alert the users and allow them to correct the problems.

APEX has a built-in Validations mechanism, which is a server-side mechanism. Currently, APEX doesn't include an out-of-the-box client-side Validations mechanism, although it allows us to develop one for ourselves based on JavaScript. It is up to us, as developers, to determine the proper relationship between the client-side and the server-side validation mechanisms.

In this chapter, we are going to review the following issues:

• The APEX concepts regarding data validation

• How to use the APEX built-in server-side Validation mechanism

• The main principles of developing our own client-side...