Hi Frank, Seems you want a custom trigger, maybe the doc[1] can help.
[1] https://ci.apache.org/projects/flink/flink-docs-release-1.8/dev/stream/operators/windows.html#triggers Best Congxian On May 23, 2019, 23:38 +0800, Frank Wilson <fajwil...@gmail.com>, wrote: > Hi, > > Is there a way to make the count window trigger fire only once? I would like > a session window to only emit the first element it receives immediately > rather than waiting until the watermark passes the end of the window. > > Thanks, > > Frank
