It is often helpful or even essential that databases be adapted in a flexible and evolving way to users and their businesses in the computer world. The control of accessible data is also a recurrent and sensitive subject. From this point of view, developers use methods and formulas that are sometimes complex to give or restrict access to information, depending on the context or the access rights of the users.

Let’s take a simple example. In your application, you sometimes need to display a list of people. One of the columns displays their full names, but in your database, you have a first name field and a last name field. Currently, you write a formula in the list box column, and you have to manage the sorting on the column yourself. Wouldn’t it be great to have a computed field where you can define its calculation formula and sorting method, and have all the business logic inside the class and not in each interface?

Well, starting with 4D v19 R3, 4D provides a solution to this, with computed attributes.