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From Mikael Högqvist <hoegqv...@gmail.com>
Subject Re: KTable#through from window store to key value store
Date Fri, 16 Dec 2016 18:44:12 GMT
Hi Eno,

in this example it doesn't make much sense, but I could add a .mapValues
that transforms the values and the use .through to materialize a table with
the updated values.

It is possible to the access the new table as a KeyValueStore also, but it
is much less convenient and I also expected that if I have a window store
it would still be a window store after transformation/through.

Thanks,
Mikael

On Fri, Dec 16, 2016 at 6:20 PM Eno Thereska <eno.thereska@gmail.com> wrote:

> Hi Mikael,
>
> Currently that is not possible. Could you elaborate why you'd need that
> since you can query from tableOne.
>
> Thanks
> Eno
> > On 16 Dec 2016, at 10:45, Mikael Högqvist <hoegqvist@gmail.com> wrote:
> >
> > Hi,
> >
> > I have a small example topology that count words per minute (scala):
> >
> >    words
> >      .map { (key, word) =>
> >        new KeyValue(word, Long.box(1L))
> >      }
> >      .groupByKey(Serdes.String, Serdes.Long)
> >      .count(TimeWindows.of(5 * 60 * 1000L), tableOne)
> >      .through(new WindowedSerde, Serdes.Long, s"$appId-count-topic",
> > tableTwo)
> >
> > The first table, tableOne, is a WindowStore and can be accessed using
> fetch
> > on the key and time range. After using .through to forward the data to
> > another topic and table, tableTwo becomes a KeyValueStore. Is it possible
> > to keep tableTwo as a WindowStore also?
> >
> > Best,
> > Mikael
>
>

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