docs: public byte[] getBytes(int columnIndex) throws SQLException {
      checkObjectRange(columnIndex);
      if (row.lastValueWasNull()) {
        return null;
      }
      byte[] data = new byte[row.getLengthMaxFieldSize()];
      System.arraycopy(row.buf, row.pos, data, 0, row.getLengthMaxFieldSize());
      return data;
    }