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From Fabian Hueske <fhue...@gmail.com>
Subject Re: Is watermark used by joining two streams
Date Sun, 30 Jul 2017 09:16:46 GMT
Periodic and punctuated watermarks only differ in the way that they are
generated. Afterwards they are treated the same.
An operator with two input streams will always sync its own watermarks to
the watermarks of both input streams, i.e., to the "slower" watermark of
both inputs.
So if the left input says it is 12:14 and the right says it is 11:53, the
operator will have a internal time of 11:53 and emit watermarks according
to that time.

Hope that helps,

2017-07-28 15:00 GMT+02:00 xie wei <jixian01@googlemail.com>:

> Hello,
> i want to join two streams based on event time window, every stream has
> its own watermark, one has priodic watermark and the other has punctuated
> watermark.
> are the watermarks used to trigger the join? if yes, which one and how is
> it used?
> Thank you and best regards
> Wei

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