[ https://issues.apache.org/jira/browse/FLINK-20190?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
GaryGao updated FLINK-20190: ---------------------------- Summary: A New Window Trigger that can trigger window operation both by event time interval、event count (was: A New Window Trigger that can trigger window operation by event time interval、event count) > A New Window Trigger that can trigger window operation both by event time > interval、event count > ---------------------------------------------------------------------------------------------- > > Key: FLINK-20190 > URL: https://issues.apache.org/jira/browse/FLINK-20190 > Project: Flink > Issue Type: New Feature > Components: API / DataStream > Reporter: GaryGao > Priority: Major > Fix For: 1.12.0 > > > In production environment, when we are do some window operation, such as > window aggregation, using data stream api, developers are always asked to not > only trigger the window operation when the watermark pass the max timestamp > of window, but also trigger it both by fixed event time interval and fixed > count of event.The reason why we want to do this is we are looking forward to > get the frequently updated window operation result, other than waiting for a > long time until the watermark pass the max timestamp of window.This is very > useful in reporting and other BI applications. > For now the default triggers provided by flink can not close this > requirement, so I developed a New Trigger, so called > CountAndContinuousEventTimeTrigger, combine ContinuousEventTimeTrigger with > CountTrigger to do the above thing. > > To use CountAndContinuousEventTimeTrigger, you should specify two parameters > as revealed in it constructor: > {code:java} > private CountAndContinuousEventTimeTrigger(Time interval, long > maxCount);{code} > * Time interval, it means this trigger will continuously fires based on a > given time interval, the same as ContinuousEventTimeTrigger. > * long maxCount, it means this trigger will fires once the count of elements > in a pane reaches the given count, the same as CountTrigger. > -- This message was sent by Atlassian Jira (v8.3.4#803005)