This form presents and validates data without any built-in knowledge about the underlying tables. The format masks, range values, default values and constraints are dynamically picked up from the Oracle Dictionary.
In the example above, the check constraint 'emp_mgr_check' (mgr <> empno) is violated. For check constraint 'emp_mgr_check' the message 'An employee cannot manage him/her self' is registered in the message table. The form or dataset do not have any built-in knowledge about this. This implies that you can add, change or remove constraints without even recompiling your application.