Chapter 3 Building Conceptual Data Models

Changing a relationship into an associative entity

You can transform a relationship into an associative entity linked by two relationships, and then attach entity attributes to the associative entity, that you could not attach to the relationship.

The associative entity retains the name and code of the relationship, and the two new relationships handle cardinality properties.

To change a relationship directly into an associative entity:

1. Right-click a relationship symbol and select Change to Entity→Standard from the contextual menu.
   
   An associative entity with two relationships replaces the relationship. The associative entity takes the name of the original relationship.

To change a relationship into an associative entity using the Change to Entity Wizard:

1. Right-click a relationship symbol and select Change to Entity→Wizard from the contextual menu to open the Change to Entity Wizard.
2. On the Customizing Entity page, type an entity name and code, and then click Next.
3. On the first Customizing Relationship page, complete the details for the relationship that will be created between the first entity and the new entity, and then click Next.
4. On the second Customizing Relationship page, complete the details for the relationship that will be created between the new entity and the second entity, and then click Finish.
   
   The associative entity with two relationships replaces the relationship.

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