anchor.diff:  a +.+ (dot) and the embedded property (recursively for several levels of embedded objects).
   
   The MongoDB datastore treats dots specifically as it transforms them into nested documents.
  -If you want to override one column name but still keep the nested structure, don't forget the dots.
  +If you want to override one column name and still keep the nested structure, don't forget the dots.
   
   That's a bit abstract, so let's use an example.
   
  
positive.code:         "provider": "Santa Claus Inc.",
          "delays": "1"
      }
  }
  ----
  
  If you share the same embeddable in different places, you can use JPA's +@AttributeOverride+
  to override columns from the embedding side.
  ====
  
  ==== Associations
  
negative.code:     String city;
  }
  
  // both columns overridden from the embedding side
  @Embeddable
  public DeliveryProvider {
      String name;
      Integer expectedDelaysInDays;
  }
  
  // do not use dots in the overriding
  // and mix levels (bad form)
  @Embedded
  class CreditCardType {
      String merchant;
      @Column(name="network")
      String network;
  }
  ----
  
  