A non-identifying relationship is a relationship between two entities in which an instance of the child entity is not identified through its association with a parent entity, which means the child entity is not dependent on the parent entity for its identity and can exist without it. In a non-identifying relationship, one instance of the parent entity is related to multiple instances of the child.
You can create the following types of non-identifying relationships:
You can set the default non-identifying null option in the Model Editor.
You can also use non-identifying relationships to create recursive relationships.
You can create a non-identifying relationship when you add a relationship using the Relationships editor, on the diagram window, or using the Model Explorer.
Note: Primary key attributes are automatically migrated from a parent entity to a child entity, so you do not need to enter any foreign keys in the child.
Copyright © 2017 erwin Inc.
All rights reserved.
|
|