instance method preserve_original_encrypted

# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 93
          def preserve_original_encrypted(name)
            original_attribute_name = "#{ORIGINAL_ATTRIBUTE_PREFIX}#{name}".to_sym

            if !ActiveRecord::Encryption.config.support_unencrypted_data && !column_names.include?(original_attribute_name.to_s)
              raise Errors::Configuration, "To use :ignore_case for '#{name}' you must create an additional column named '#{original_attribute_name}'"
            end

            encrypts original_attribute_name
            override_accessors_to_preserve_original name, original_attribute_name
          end