Jason Dere created HIVE-19489:
---------------------------------
Summary: Disable stats autogather for external tables
Key: HIVE-19489
URL: https://issues.apache.org/jira/browse/HIVE-19489
Project: Hive
Issue Type: Sub-task
Components: Statistics
Reporter: Jason Dere
Assignee: Jason Dere
Hive auto-gather of table statistics can result in incorrect generation of
stats (and the stats being marked as accurate) in the case of external tables
where the data is being written by external apps.
To avoid this issue, stats autogather will be disabled on external tables when
loading/inserting into a table with existing data, if
HIVE_DISABLE_UNSAFE_EXTERNALTABLE_OPERATIONS is enabled. In this situation,
users should rely on explicitly calling ANALYZE TABLE on their external tables
to make sure the stats are kept up-to-date.
Autogather of stats will still be allowed to occur on external tables in the
case of INSERT OVERWRITE or LOAD DATA OVERWRITE, since the existing data is
being removed and so the stats calculated on the inserted/loaded data should be
accurate.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
