diff
Compares the log events found in your requested time period with the log events from a previous time period of equal length. This way, you can look for trends and find whether specific log events are new.
Add a modifier to the diff command to specify the time period
                        that you want to compare with:
- 
                            diffcompares the log events in the currently selected time range to the log events of the immediately preceding time range.
- 
                            diff previousDaycompares the log events in the currently selected time range to the log events from the same time the preceding day.
- 
                            diff previousWeekcompares the log events in the currently selected time range to the log events from the same time the preceding week.
- 
                            diff previousMonthcompares the log events in the currently selected time range to the log events from the same time the preceding month.
For more information, see Compare (diff) with previous time ranges.