There's nothing stopping me assigning timestamps and generating watermarks on
a keyed stream in the implementation and the KeyedStream API supports it. It
appears the underlying operator that gets created in
DataStream.assignTimestampsAndWatermarks() isn't key-aware and globally
tracks timestamps.
Hi Jordan,
it is not possible to generate watermarks per key. This feature has been
requested a couple of times but I think there are no plans to implement
that.
As far as I understand, the management of watermarks would be quite
expensive (maintaining several watermarks, purging watermarks of
