code: private void applyUpdates(DBTransaction dbTran) {
          Map<String, Map<String, List<DColumn>>> colUpdatesMap = dbTran.getColumnUpdatesMap();
          for (String storeName : colUpdatesMap.keySet()) {
              updateTableColumnUpdates(storeName, colUpdatesMap.get(storeName));
          }
          
          Map<String, Map<String, List<String>>> colDeletesMap = dbTran.getColumnDeletesMap();
          for (String storeName : colDeletesMap.keySet()) {
              updateTableColumnDeletes(storeName, colDeletesMap.get(storeName));
          }
          
          Map<String, List<String>> rowDeletesMap = dbTran.getRowDeletesMap();
          for (String storeName : rowDeletesMap.keySet()) {
              for (String rowKey : rowDeletesMap.get(storeName)) {
                  Map<String, AttributeValue> key = DynamoDBService.makeDDBKey(rowKey);
                  m_service.deleteRow(storeName, key);
              }
          }
      }
docs: ----- Private methods