Blocker Description
As of now, we do not store the list of cols to index anywhere. We have this https://issues.apache.org/jira/browse/HUDI-8232 ticket to add the support.
once we have the support, on the query side pruning, we should avoid looking up in cols stats if a col is not indexed w/ col stats only. As of now, we just lookup in col stats for every col in the query predicate.