In unidirectional association, we will have navigation only in one direction, i.e, only one side of the association will have the reference to the other side. The one side of the association will implement one of the collection interfaces, if it has the reference to the other entity.
In many to many relationship, multiple target objects can have relationship with multiple source objects. Let’s consider CD and Artist. So only one Artist can write multiple CD or a CD can be written by multiple Artists. So we will create three tables CD, Artist and CDArtist in the database and we will see how many-to-many relationship works step by step. Read More