Could anyone advise please what is this Stream-based Interaction History? Does it run on Kafka instead of DB? How is it "Stream-based"? Is there any documentation available on how it works in more detail?
Check the dataset pxinteractionstream. It is indeed running on Kafka as part of the Pega stream service. You need to enable RealTime dataflow service as well. See this starting link for Pega Stream Service:
After some experimenting it seems like the interactionHistory/AggregatesOnlyMode controls which back-end is used for the Interaction History Summaries/Aggregations.
If set to "true" -- the "pxInteractionsStream" is used, else -- the default "pxInteractionHistory" is chosen.
But somehow I wasn't able to get this working on 8.2.1. It works as expected on 8.3.0.