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From Aljoscha Krettek <aljos...@apache.org>
Subject Re: Window function - iterator data
Date Wed, 10 Aug 2016 08:48:58 GMT
Hi,
Kostas is right in that the elements are never explicitly sorted by
timestamp. In some cases they might not even be iterated in the order that
they were added so I would normally assume the order of the elements to be
completely arbitrary.

Cheers,
Aljoscha

On Wed, 10 Aug 2016 at 09:44 Kostas Kloudas <k.kloudas@data-artisans.com>
wrote:

> Hi Paul,
>
> Elements are returned in the order they were added in the window.
> No sorting on timestamp is performed.
>
> Hope this helps,
> Kostas
>
> On Aug 9, 2016, at 10:22 PM, Paul Joireman <paul.joireman@physiq.com>
> wrote:
>
> When you are using a window function the docs:
>
>
> https://ci.apache.org/projects/flink/flink-docs-master/apis/streaming/windows.html#windowfunction---the-generic-case
>
> state that
>
> A WindowFunction gets an Iterable containing all the elements of the
> window being processed
>
> If the input data stream is timestamped using event times where the events
> can come in out of chronological order, are the events returned by the
> interator the same order as they were added?  Or does the window sort them
> internally on timestamp and return them through the iterator in timestamp
> chronological order?
>
> Paul
>
>
>

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