Hi, I'm wondering impala team has any plans for approximate topN for single dimension.
My Web analytic system mostly serves top n urls. Such a "GROUP BY url ORDER BY pageview LIMIT n" is slow especially for high-cardinality field. Approximate topN can be used instead of GroupBy for single dimension with extremely lower latency. Elastisearch, Druid, and Clickhouse already provide this feature. It would be great if I can use it on Druid. Thanks. Regards, Jason
