The EJB specification allows you to map an entity bean to multiple tables. You do this by using the @SecondaryTable annotation.

The org.jboss.tutorial.secondary.bean.Customer entity maps its address properties to a separate ADDRESS table. The first thing it does is define the secondary table.

			
@Entity
@Table(name = "CUSTOMER")
@SecondaryTable(name = "EMBEDDED_ADDRESS", join = {@JoinColumn(name = "ADDRESS_ID")})
public class Customer implements java.io.Serializable
{
}
			
		

The @JoinColumn of the secondary table must match the value of the Customer's primary key. To map individual properties to a secondary table you use the secondaryTable member value of @Column.

			
@Column(name = "STREET", secondaryTable = "EMBEDDED_ADDRESS")
public String getStreet()
{
   return street;
}