[ 
https://issues.apache.org/jira/browse/HIVE-22925?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Attila Magyar updated HIVE-22925:
---------------------------------
    Status: Patch Available  (was: Open)

> Implement TopNKeyFilter efficiency check
> ----------------------------------------
>
>                 Key: HIVE-22925
>                 URL: https://issues.apache.org/jira/browse/HIVE-22925
>             Project: Hive
>          Issue Type: Bug
>          Components: Hive
>            Reporter: Attila Magyar
>            Assignee: Attila Magyar
>            Priority: Major
>             Fix For: 4.0.0
>
>         Attachments: HIVE-22925.1.patch, HIVE-22925.2.patch, 
> HIVE-22925.3.patch
>
>
> In certain cases the TopNKey filter might work in an inefficient way and adds 
> extra CPU overhead. For example if the rows are coming in an descending order 
> but the filter wants the top N smallest elements the filter will forward 
> everything.
> Inefficient should be detected in runtime so that the filter can be disabled 
> of the ration between forwarder_rows/total_rows is too high.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

Reply via email to