anchor.diff:  }
   ----
   
  -associations_AccountOwner_BankAccount collection 
  +associations_AccountOwner_BankAccount collection
   
   [source, JSON]
   ----
  
positive.code:   "_id" : {
      "bankAccounts_id" : "account_1"
    },
    "rows" : [ "owner_1" ] 
  }
  {
    "_id" : {
  
negative.code: ----
  ====
  
  .Bidirectional many-to-one
  ====
  [source, JAVA]
  ----
  