@Test
  public void groupByNaturalMonthTest4() {
    String[] expectedHeader = new String[] {TIMESTAMP_STR, sum("root.sg1.d1.temperature")};
    String[] retArray = {"01/31/2021:00:00:00,28.0,", "02/28/2021:00:00:00,31.0,"};
    resultSetEqualTest(
        "select sum(temperature) from root.sg1.d1 GROUP BY ([2021-01-31, 2021-03-31), 1mo)",
        expectedHeader,
        retArray,
        df,
        currPrecision);
  }
StartTime: 2021-01-31 00:00:00, EndTime: 2021-03-31 00:00:00. First Month with 28 days, Second
month with 31 days
integration-test/src/test/java/org/apache/iotdb/db/it/groupby/IoTDBGroupByNaturalMonthIT.java