anchor.diff:            }
   
             if (select.sorts[fieldName] == 'ASC') {
  -            mongoSelector = mongoSelector.sortBy(fieldName, descending:false);
  +            mongoSelector = mongoSelector.sortBy(fieldName, descending: false);
             } else {
  -            mongoSelector = mongoSelector.sortBy(fieldName, descending:true);
  +            mongoSelector = mongoSelector.sortBy(fieldName, descending: true);
             }
           }
         }
  
positive.code:   Future<int> getNextSequence(Table table, Field field) {
      Completer completer = new Completer();
  
      log.finest('Get next sequence:' + table.toString() + ' ' +
      field.toString());
  
      String seqName = "${table.tableName}_${field.fieldName}_seq";
  
      Map command = {
          'findAndModify': 'counters',
          'query': {
              '_id': seqName
          },
          'update': {
              r'$inc': {
                  'seq': 1
              }
          },
          'new': true
      };
  
      _connection.executeDbCommand(
          mongo_connector.DbCommand.createQueryDbCommand(_connection, command))
      .then((Map result) {
        log.finest('Get next sequence result:');
        log.finest(result);
  
  
negative.code:         var value = result['value']['seq'];
          completer.complete(value);
        }
      }).catchError((e) {
        log.shout('Get next sequence error:', e);
        completer.completeError(e);
      });
  