@ConstantFunction(name = "milliseconds_sub", argTypes = {DATETIME, INT}, returnType = DATETIME, isMonotonic = true)
    public static ConstantOperator millisecondsSub(ConstantOperator date, ConstantOperator millisecond) {
        return ConstantOperator.createDatetimeOrNull(date.getDatetime().minus(millisecond.getInt(), ChronoUnit.MILLIS));
    }
@Test
    public void millisecondsSub() {
        assertEquals("2015-03-23T09:23:54.990",
                ScalarOperatorFunctions.millisecondsSub(O_DT_20150323_092355, O_INT_10).getDatetime().toString());
    }