Keeping latest data point in a data stream variable

[Biplob Biswas <re...@gmail.com>]

Hi,

I want to keep the latest data point which is processed in a datastream
variable. So technically I need just one value in the variable and discard
all the older ones.

Can this be done somehow? I was thinking about using filters but i don't
think i can use it for this scenario.
Any ideas as to how to do something like this is really appreciated.

Thanks a lot
Biplob



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Re: Keeping latest data point in a data stream variable

[Robert Metzger <rm...@apache.org>]

Hi Biplob,

would you like to send the last value somewhere?
is there a way of detecting when the stream ends? (Something like a marker
element, or could you use a timeout?)

Anyways, what you can do is use a flatMap() function, always store the
current element. Once the stream is over, you emit the last element.

On Tue, Jun 21, 2016 at 11:45 AM, Biplob Biswas <re...@gmail.com>
wrote:

> Hi,
>
> I want to keep the latest data point which is processed in a datastream
> variable. So technically I need just one value in the variable and discard
> all the older ones.
>
> Can this be done somehow? I was thinking about using filters but i don't
> think i can use it for this scenario.
> Any ideas as to how to do something like this is really appreciated.
>
> Thanks a lot
> Biplob
>
>
>
> --
> View this message in context:
> http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Keeping-latest-data-point-in-a-data-stream-variable-tp7642.html
> Sent from the Apache Flink User Mailing List archive. mailing list archive
> at Nabble.com.
>