@Override
  protected void clearBitMap() {
    for (int i = 0; i < dataTypes.size(); i++) {
      if (bitMaps != null) {
        List<BitMap> columnBitMaps = bitMaps.get(i);
        if (columnBitMaps != null) {
          columnBitMaps.clear();
        }
      }
    }
  }
Delete points in a specific column.

@param lowerBound deletion lower bound
@param upperBound deletion upper bound
@param columnIndex column index to be deleted
@return Delete info pair. Left: deletedNumber int; right: ifDeleteColumn boolean
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/utils/datastructure/AlignedTVList.java