[jira] [Commented] (HIVE-3777) add a property in the partition to figure out if stats are accurate

["Sambavi Muthukrishnan (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HIVE-3777?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13526143#comment-13526143 ] 

Sambavi Muthukrishnan commented on HIVE-3777:
---------------------------------------------

I agree with the idea of adding this Partition level property so we can ensure stats are kept up-to-date. Seems like we should set it to be false when we update the metadata for the partition at time of overwrite/insert into (transactionally). Since we just overwrite the files, I suppose we cant guarantee that the property reflects the correct value unless we conservatively set it to false before-hand, and then update it to true whenever the stats are computed next. Comments?
                
> add a property in the partition to figure out if stats are accurate
> -------------------------------------------------------------------
>
>                 Key: HIVE-3777
>                 URL: https://issues.apache.org/jira/browse/HIVE-3777
>             Project: Hive
>          Issue Type: Improvement
>          Components: Query Processor
>            Reporter: Namit Jain
>
> Currently, stats task tries to update the statistics in the table/partition
> being updated after the table/partition is loaded. In case of a failure to 
> update these stats (due to the any reason), the operation either succeeds
> (writing inaccurate stats) or fails depending on whether hive.stats.reliable
> is set to true. This can be bad for applications who do not always care about
> reliable stats, since the query may have taken a long time to execute and then
> fail eventually.
> Another property should be added to the partition: areStatsAccurate. If hive.stats.reliable is
> set to false, and stats could not be computed correctly, the operation would
> still succeed, update the stats, but set areStatsAccurate to false.
> If the application cares about accurate stats, it can be obtained in the 
> background.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira