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Let’s imagine, that there are two parking projects in timezones UTC+0 and UTC+4. Two cars get into their own local parking at midnight between Monday and Tuesday by the 2nd project time (00the same moment on Monday 20:01:00+0400:00 (UTC time).
With the use of group_by_interval=1hour, we will see in the result for both projects the same: both cars have come in on Monday at 20:01:00+00 (UTC time for 00:01:00+04:00).
The opposite case if it is passed the argument group_by_interval=day is passed, because the same moment of entering cars into the parking has happened on different days in local timezones:
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