Assignment for objects – PB Docs 2019

Declaring an object variable declares an object reference:

Using the CREATE statement creates an instance of the
object:

When you assign one object variable to another, a reference to the
object instance is copied. Only one copy of the object exists:

Ancestor and descendant
objects

Assignments between ancestor and descendant objects occur in the
same way, with an object reference being copied to the target
object.

Suppose that uo_emp_data is an ancestor user object of
uo_emp_active and uo_emp_inactive.

Declare variables of the ancestor type:

Create an instance of the descendant and store the reference in
the ancestor variable:

Assigning uo_emp1 to uo_emp2 makes both variables refer to one
object that is an instance of the descendant uo_emp_active:

For information about passing objects as function arguments, see
Passing arguments to
functions and events.