Chapter 3 Building Conceptual Data Models

Making inheritance links mutually exclusive

When an inheritance link is mutually exclusive between children, 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.

To make an inheritance link mutually exclusive:

1. Open an inheritance property sheet:
   
2. Select the Mutually Exclusive Children check box, and then click OK to return to the diagram.
   
   The mutually exclusive inheritance links display an X on the half-circle symbol.
   

In the diagram above, the inheritance link is mutually exclusive, meaning that an account is either checking or savings, but never both.

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