[JakaJancar]

We have stored many terabytes of unaggregated transaction records in Vertica and analyzed large subsets fully ad-hoc, on-the-fly in less than 5s. We have also used BigQuery to directly power dashboards with few-second response times, also analyzing billions of records at a time.

On the other hand, we both build and use summary tables with Spark. (in a relational format to boot, and using Spark SQL).

I think you would benefit from re-evaluating the assumptions you made 4-5 years ago.