public int compareTo(int elementNum, HiveIntervalDayTime intervalDayTime) {
    return asScratchIntervalDayTime(elementNum).compareTo(intervalDayTime);
  }
Compare row to HiveIntervalDayTime.
We assume the entry has already been NULL checked and isRepeated adjusted.
@param elementNum
@param intervalDayTime
@return -1, 0, 1 standard compareTo values.
storage-api/src/java/org/apache/hadoop/hive/ql/exec/vector/IntervalDayTimeColumnVector.java