Hi Rock, There is an inaccurate description in last response. I don't think a watermark of 0 clock is needed to get the accurate calculation result. The watermark of 0 clock only helps to generate the result you want immediately.
Thanks, Biao /'bɪ.aʊ/ On Tue, 26 Nov 2019 at 18:10, Biao Liu <mmyy1...@gmail.com> wrote: > Hi Rock, > > From my understanding, what you want is a one-day time based window which > start at 0 clock. > Actually the one-day time-based window (like Jack mentioned) starts at the > beginning of day (0:00). You don't need to do anything special. > > If you are using event time window (since you mentioned watermark), the > only thing you need to do is generating the correct watermark. > For example, to get the accurate one-day aggregation (you don't want to > involve any record from next day), a watermark of 0 clock might be needed. > You may find the answer in [1][2]. > > [1] > https://ci.apache.org/projects/flink/flink-docs-release-1.9/dev/event_timestamps_watermarks.html > [2] > https://ci.apache.org/projects/flink/flink-docs-release-1.9/dev/event_timestamp_extractors.html > > Thanks, > Biao /'bɪ.aʊ/ > > > > On Tue, 26 Nov 2019 at 17:46, Jark Wu <imj...@gmail.com> wrote: > >> Hi Rock, >> >> Sorry, I don't fully understand what you want. >> If you want a tumbling window which covers one day, >> you can use `KeyedStream#timeWindow(Time.days(1))` which covers from UTC >> 00:00~24:00. >> >> Best, >> Jark >> >> >> On Tue, 26 Nov 2019 at 17:20, Caizhi Weng <tsreape...@gmail.com> wrote: >> >>> Hi Rock, >>> >>> I think you can write your own trigger which fires when the date of the >>> process time of the current record is different from that of the last >>> record. >>> >>> Pinging @Jark Wu for a more professional answer. >>> >>> Rock <downsidem...@qq.com> 于2019年11月26日周二 下午3:37写道： >>> >>>> I need my job to aggregator every device's mertic as daily report.But I >>>> did not find a window can cover exactly one day,or let everyday's beginning >>>> as watermark .Should I custom a window or any other way to achieve? >>>> >>>
