Chapter 4 Building Conceptual Data Models
In a one-to-one relationship, you can define one direction of the relationship as dominant. If you define a dominant direction, the one-to-one relationship generates one reference in the PDM. The dominant entity becomes the parent table. If you do not define a dominant direction, the one-to-one relationship generates two references.
To define a dominant relationship:
For example, in the property sheet below, the Author to Picture direction is dominant in the relationship.
The relationship pictured here shows the one-to-one relationship.
In a PDM, this relationship generates the following reference: Author is the parent table, and its primary key migrates to the Picture table as foreign key.
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