How to Make Fields Non-Displayed
Non-displayed fields can be used as local variables. This is a good idea if you think you might want to display the value at a later point in time, perhaps for testing purposes. You can then easily set the field to non-displayed without making any further changes.
If you are sure you just want a "hidden" variable, consider using the Variables control class or one of its subclasses.
If you want to make a database column non-displayed, consider omitting the column from the window's underlying query. This gives better performance because values are no longer physically retrieved from database.
To make a field non-displayed:
To facilitate easy selection, make sure the Selection Filter option from the View menu is switched on.
Non-displayed Query Column objects will no longer show up in the Object tree as children of the Column Box object. They can be accessed, however, as children of the Query object.