Hi lec ssmi, It's a good question. In blink planner, we use code gen to handle watermark expression. And in `WatermarkAssignerOperator` we calculate current watermark when each element comes in. If the watermark - lastEmitedWatermark > watermark interval, we will emit the new watermark.
So it's neither `PeriodicWatermark` nor `PunctuatedWatermark`. lec ssmi <[email protected]> 于2020年4月17日周五 下午3:12写道： > Hi: > In sql API , the declaration of watermark is realized by ddl statement > . But which way is it implemented? > * PeriodicWatermark * or *PunctuatedWatermark*？ > There seems to be no explanation on the official website. > > Thanks. > -- Benchao Li School of Electronics Engineering and Computer Science, Peking University Tel:+86-15650713730 Email: [email protected]; [email protected]
