[ https://issues.apache.org/jira/browse/HIVE-6873?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Remus Rusanu updated HIVE-6873: ------------------------------- Attachment: HIVE-6873.2.patch Allow for COUNT(DISTINCT expr) wich happens to work, by accident, dur to how reduce side handles the aggregate merge for COUNT(DISTINCT) > DISTINCT clause in aggregates is handled incorrectly by vectorized execution > ---------------------------------------------------------------------------- > > Key: HIVE-6873 > URL: https://issues.apache.org/jira/browse/HIVE-6873 > Project: Hive > Issue Type: Bug > Components: Query Processor > Affects Versions: 0.13.0, 0.14.0 > Reporter: Remus Rusanu > Assignee: Remus Rusanu > Attachments: HIVE-6873.1.patch, HIVE-6873.2.patch > > > The vectorized aggregates ignore the DISTINCT clause. This cause incorrect > results. Due to how GroupByOperatorDesc adds the DISTINCT keys to the overall > aggregate keys the vectorized aggregates do account for the extra key, but > they do not process the data correctly for the key. the reduce side the > aggregates the input from the vectorized map side to results that are only > sometimes correct but mostly incorrect. HIVE-4607 tracks the proper fix, but > meantime I'm filing a bug to disable vectorized execution if DISTINCT is > present. Fix is trivial. -- This message was sent by Atlassian JIRA (v6.2#6252)