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From Aljoscha Krettek <aljos...@apache.org>
Subject Re: Behaviour of CountWindowAll
Date Tue, 05 Jan 2016 11:02:04 GMT
I’m afraid this is not possible right now. I’m also not sure about the Evictors as a whole.
Using them makes window operations very slow because all elements in a window have to be kept,
i.e. window results cannot be pre-aggregated.

> On 15 Dec 2015, at 12:23, Radu Tudoran <radu.tudoran@huawei.com> wrote:
> Hi,
> I believe this question might have been asked before - so sorry for repeating it (I just
did not find the discussion on the mailing list).
> Is it possible somehow to create a new DataStream from the elements that are evicted
from a window?
> A simple use case for this is: 
> We have data coming from a sensor every second. We want to compute all the times the
average on the last 5 seconds and on the interval from 5 seconds ago until 10 seconds ago.
> I would be interested in how the data evicted from the main window that keeps the fresh
data could be feed into a new stream on which I could apply again a window of 5 seconds.
> (Having a 10 seconds window and selecting only the most ancient 5 second data is not
a viable option) 
> Regards,

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