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Re: TPCDS query degrade with hive-3.1.2 because of wrong estimation for reducers

Based on the plan, filtered output in map-1 had mis-estimates and also groupby operators have large misestimates. This is causing the number of reducers to be estimated as "4" which is less for this query. Due to the partition factor of tez, it ends up with 8 reducer slots at runtime for hive 3.x.