Tianyi Wang created IMPALA-6822: ----------------------------------- Summary: Provide a query option to not shuffle on distinct exprs Key: IMPALA-6822 URL: https://issues.apache.org/jira/browse/IMPALA-6822 Project: IMPALA Issue Type: Improvement Affects Versions: Impala 3.0, Impala 2.13.0 Reporter: Tianyi Wang
After IMPALA-4794, in a distinct aggregation, data will be shuffled on grouping exprs and distinct expr. It works well if the NDV of grouping exprs is low, but is an regression otherwise. We should provide a query operation to disable IMPALA-4794 and probably look to do smarter planning in the future. -- This message was sent by Atlassian JIRA (v7.6.3#76005)