Inheritances (CDM/LDM)

An inheritance allows you to define an entity as a special case of a more general entity. The general, or supertype (or parent) entity contains all of the common characteristics, and the subtype (or child) entity contains only the particular characteristics.

In the example below, the Account entity represents all the bank accounts in the information system. There are two subtypes: checking accounts and savings accounts.

The inheritance symbol displays the inheritance status:

• Creating an Inheritance
  You can create an inheritance in any of the following ways:
• Inheritance Properties
  You can modify an object's properties from its property sheet. To open an inheritance property sheet, double-click its diagram symbol or its Browser entry in the Inheritances folder.
• Making Inheritance Links Mutually Exclusive
  When an inheritance link is mutually exclusive, one occurrence of the parent entity cannot be matched to more than one child entity. This information is for documentation only and has no impact in generating the PDM.
• Identifier Migration Through an Inheritance (LDM)
  In an LDM, primary identifiers of a parent entity always migrate to the child entity. The migration of other attributes of the parent entity depends on which inheritance option is selected.