Cascading delete concept

An elegant cascading delete concept reduces the amount of explicit object deletions in your source code and helps to keep the database clean of dispensable objects.

We distinguish strong and weak entity classes:

• Strong entity classes are never subject of cascading deletes. As long as every entity class is a strong entity class, no object is deleted automatically by the container.
• Weak entity classes may be subject of cascading deletes. This is the case if the class participates in one or more compositions. If a weak entity object is not part of a composite object, it will be deleted automatically.