Form levels form the basic framework of the hierarchy of an application form. Form levels that are hierarchically dependent on one another (parent-child dependency) have a 1:n relationship with one another. This means that for each entry in a form level there are several related entries for the form level below (for example, customer and his flight bookings). However, form levels at the same level have no hierarchical relationship to one another.
The hierarchical relationships of the levels are
defined in the form class and cannot be changed. However, you can use the same
form level more than once in the hierarchy (duplication).
The name of a form level and the DDIC structure below it is defined in the
corresponding form class and cannot be changed.