Operational tasks are on you, there are scripts that can be found to help out with auto-scaling the cluster but that also does put load on the cluster because i

Operational tasks are on you, there are scripts that can be found to help out with auto-scaling the cluster but that also does put load on the cluster because it has to do a lot of work underneath when scaling down to rearrange splits. I would only recommend scaling up. All aggregations are done outside the DB level so yes your client would most likely have to create the logic for the rollup.