We tried creating a table partitioned by composite range
PARTITION BY RANGE(insert_date, report_date, dwbuid)

The thinking was that by having both dates part of range partition will allow users to have queries that hit either insert_date or report_date to get same performance.
it turns out that queries that reference insert_date are much faster than the ones
that hit report_date.

Queries that hit report_date do a full index scan. (slow) 2 min
queries that hit insert_date hit the correct partition ranges. (fast) 10 sec
Need a way to have both dates have the same weight regardless of the order of which they are enumerated in the partitioning statement.