Chapter 4 Building Conceptual Data Models

Creating an associative entity using the Change to Entity Wizard

You can use the Change to Entity wizard to transform a relationship into an associative entity linked by two relationships.

You create the associative entity in three stages. Each stage corresponds to a page in the wizard process. You move through each stage by clicking the Next button.

You can enter the following information for each stage of the wizard:

Stage Description
Customizing entity You type the name and code for the new entity. You can also type a description in the Comment box
Customizing Relationship (New entity to first entity) You type the name and code for the relationship that will be created between the first entity and the new entity. The first entity is defined as Entity 1 in the property sheet for the original relationship. You can also enter a role name for the relationship and a cardinality value
Customizing Relationship (New entity to second entity) You type the name and code for the relationship that will be created between the new entity and the second entity. The second entity is defined as Entity 2 in the property sheet for the original relationship. You can also enter a role name for the relationship and a cardinality value

Steps To create an associative entity using the Change to Entity Wizard:

  1. Right-click a relationship symbol.

    A contextual menu is displayed.
  2. Select→Change to Entity→Wizard to display the Customizing Entity page.
  3. Type an entity name and an entity code.
  4. Click Next.

    The Customizing Relationship page is displayed.
  5. Fill in details for the first entity to new entity relationship.
  6. Click Next.

    The second Customizing Relationship page is displayed.
  7. Fill in details for the new entity to second entity relationship.
  8. Click Finish.

    The associative entity with two relationships replaces the relationship.

 

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