/**
   * It computes the value cardinality of a tuple range.
   *
   * @return
   */
  public static BigDecimal computeCardinalityForAllColumns(
      Schema schema, TupleRange range, boolean inclusive) {
    Tuple start = range.getStart();
    Tuple end = range.getEnd();
    Column col;

    BigDecimal cardinality = new BigDecimal(1);
    BigDecimal columnCard;
    for (int i = 0; i < schema.getColumnNum(); i++) {
      col = schema.getColumn(i);
      columnCard = computeCardinality(col.getDataType(), start.get(i), end.get(i), inclusive);

      if (new BigDecimal(0).compareTo(columnCard) < 0) {
        cardinality = cardinality.multiply(columnCard);
      }
    }

    return cardinality;
  }
 @Override
 public int compare(TupleRange left, TupleRange right) {
   return -(left.compareTo(right));
 }