While business components provide the complete set of business logic for a given business entity, business objects group them together in hierarchical relationships by establishing the context of a primary business component and using link object definitions to glue one parent and one child business component together.

So-called 1:M links use foreign key—primary key relationships. M:M links reference intersection tables to support the storage of related primary keys.

When we wish to establish new child business components for existing parent business components, we must first create the new child business component, then a new 1:M link definition, and finally add the new child business component to the business object where the parent business component is the primary business component.

In the next chapter, we will discuss the concept of static and dynamic pick lists.