Validation rules

If any of these rules are violated, the transaction is rejected:

• Either bob_id or old_external_key must be specified, not both.
• If present, transaction must contain a valid bob_id. An external key need not exist for the specified BOb ID. If this does exist, it is overwritten by new_external_key. The bob_id option is intended for adding new external keys.
• If present, transaction must contain a valid old_external_key. The new_external_key replaces the old_external_key. The old_external_key option is for changing existing external keys.
• External keys must be unique within a BOb type.