Count Window Trigger that only fires once

[Frank Wilson]

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

[Congxian Qiu]

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 <[hidden email]>, 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