Question about Streaming Windows in Join

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Question about Streaming Windows in Join

Aljoscha Krettek-2
Hi,
I noticed that the way you specify windows for a join differs from the
way you specify windows on a DataStream. Maybe I'm missing something
here. :D

If not, is there are reason for this behaviour? Are there any plans to
consolidate?

Cheers,
Aljoscha
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Re: Question about Streaming Windows in Join

Gyula Fóra-2
Hey Aljoscha,

This is not an accident :D

The reason behind only supporting time-window joins at the moment, is
because time-window-joins can be implemented in a completely non-blocking
fashion arising from the global nature of time.

All other windows would need to be matched properly which inevitably needs
some blocking of channels or buffering up windows, neither of which is very
scalable for streams.

At some point I will try to work on unifying this one way or another but we
need to come up with some scalable solution for this.

Cheers,
Gyula

On Wed, Mar 25, 2015 at 4:28 PM, Aljoscha Krettek <[hidden email]>
wrote:

> Hi,
> I noticed that the way you specify windows for a join differs from the
> way you specify windows on a DataStream. Maybe I'm missing something
> here. :D
>
> If not, is there are reason for this behaviour? Are there any plans to
> consolidate?
>
> Cheers,
> Aljoscha
>