Item 56: How to JOIN FETCH an @ElementCollection Collection
Especially when defining a unidirectional one-to-many association to a Basic type (e.g., String) or Embeddable type, JPA has a simple solution in the form of @ElementCollection. These types are mapped in a separate table that can be customized via @CollectionTable. Let’s assume that an online bookstore shopping cart is mapped via the ShoppingCart entity and the embeddable Book is mapped via @ElementCollection, as shown in Figure 5-1.
Figure 5-1
The @ElementCollection table relationship
The relevant part is the @ElementCollection ...
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