Hi >From the description, you use window operator, and set to event time. then you should call `DataStream.assignTimestampsAndWatermarks` to set the timestamp and watermark. Window is triggered when the watermark exceed the window end time
Best, Congxian kant kodali <kanth...@gmail.com> 于2020年3月4日周三 上午5:11写道： > Hi All, > > I have a custom aggregated state that is represent by Set<Long> and I have > a stream of values coming in from Kafka where I inspect, compute the custom > aggregation and store it in Set<Long>. Now, I am trying to figureout how do > I print the updated value everytime this state is updated? > > Imagine I have a Datastream<Set<Long>> > > I tried few things already but keep running into the following exception. > Not sure why? Do I need to call assignTimestampsAndWatermark? I thought > watermarks are not mandatory in Flink especially when I want to keep this > aggregated state forever. any simple code sample on how to print the > streaming aggregated state represented by Datastream<Set<Long>> will be > great! You can imagine my Set<Long> has a toString() method that takes > cares of printing..and I just want to see those values in stdout. > > Caused by: java.lang.RuntimeException: Record has Long.MIN_VALUE timestamp > (= no timestamp marker). Is the time characteristic set to > 'ProcessingTime', or did you forget to call > 'DataStream.assignTimestampsAndWatermarks(...)'? >
