You can define containment relationships and choose how they are implemented using the Containment wizard.
Use containment relations when you want one business object to contain one or more other business objects.
When you query the containing object, the contained objects are also returned. You can also add a new business object and add multiple contained objects in a single transaction. For example, SpecBObj can contain multiple SpecFormatBObj objects.
The containing business object is known as the parent and the contained objects are called child objects.