[ 
https://issues.apache.org/jira/browse/HIVE-1605?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ning Zhang updated HIVE-1605:
-----------------------------

    Attachment: HIVE-1605.patch

Passed all test except scriptfile1.q in TestMinimrCliDriver in hadoop 0,20. 
This test also failed on trunk. 

> regression and improvements in handling NULLs in joins
> ------------------------------------------------------
>
>                 Key: HIVE-1605
>                 URL: https://issues.apache.org/jira/browse/HIVE-1605
>             Project: Hadoop Hive
>          Issue Type: Improvement
>            Reporter: Ning Zhang
>            Assignee: Ning Zhang
>         Attachments: HIVE-1605.patch
>
>
> There are regressions in sort-merge map join after HIVE-741. There are a lot 
> of OOM exceptions in SMBMapJoinOperator. This caused by the HashMap 
> maintained for each key to remember whether it is NULL. This takes too much 
> memory when the tables are large. 
> A second issu is in handling NULLs if the join keys are more than 1 column. 
> This appears in regular MapJoin as well as SMBMapJoin. The code only checks 
> if all the columns are NULL. It should return false in match if any joined 
> value is NULL. 

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Reply via email to