Hi Christophe,
if you don't have a way to recompute the key from the aggregation result,
then you have to write an aggregation function which explicitly keeps it
(e.g. a tuple value where the first entry is the key and the second the
aggregate value).
Cheers,
Till
On Fri, Jan 5, 2018 at 5:51 PM,
Hi all,
I'm sourcing from a Kafka topic, using the key of the Kafka message to key
the stream, then doing some aggregation on the keyed stream.
Now I want to sink back to a different Kafka topic but re-using the same
key. The thing is that my aggregation "lost" the key. Obviously I can make
sure
