Chapter 4 Building Conceptual Data Models

Changing an association into an associative entity

You can transform an association into an associative entity linked by two associations. The associative entity gets the name and code of the association. The two new associations handle cardinality properties.

Example

Two entities PROJECT MANAGER and CONTRACTOR are linked by the association WORKS ON PROJECT WITH:


You can represent this association with an associative entity:


The two new associations can be represented as follows:


Steps To change an association into an associative entity:

  1. Right-click an association symbol.

    The association contextual menu appears.
  2. Select Change to Entity from the contextual menu.

    An associative entity that is linked to two associations replaces the original association. The associative entity takes the name of the original association.

 

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