public void serialize(ByteBuffer buffer) {
    ReadWriteIOUtils.write(startTime, buffer);
    ReadWriteIOUtils.write(endTime, buffer);
    interval.serialize(buffer);
    slidingStep.serialize(buffer);
    ReadWriteIOUtils.write(leftCRightO, buffer);
  }
The parameter of `GROUP BY TIME`.

<p>Remember: interval and slidingStep is always in timestamp unit before transforming to
timeRangeIterator even if it's by month unit.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/plan/parameter/GroupByTimeParameter.java