You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@hive.apache.org by "Namit Jain (JIRA)" <ji...@apache.org> on 2013/01/14 09:26:13 UTC
[jira] [Commented] (HIVE-3403) user should not specify mapjoin to
perform sort-merge bucketed join
[ https://issues.apache.org/jira/browse/HIVE-3403?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13552501#comment-13552501 ]
Namit Jain commented on HIVE-3403:
----------------------------------
If one of the tables is small enough to fit in memory, there is no need to perform sort-merge join. The
policy should check that. Eventually, that check should be removed, and that should be handled by the physical
optimizer - will file a new jira for that.
I had filed https://issues.apache.org/jira/browse/HIVE-3598 for that, but since sub-query support for map-joins
has gone in, this change is more complicated. Will do the backup task in a new jira.
> user should not specify mapjoin to perform sort-merge bucketed join
> -------------------------------------------------------------------
>
> Key: HIVE-3403
> URL: https://issues.apache.org/jira/browse/HIVE-3403
> Project: Hive
> Issue Type: Bug
> Reporter: Namit Jain
> Assignee: Namit Jain
> Attachments: hive.3403.10.patch, hive.3403.11.patch, hive.3403.12.patch, hive.3403.1.patch, hive.3403.2.patch, hive.3403.3.patch, hive.3403.4.patch, hive.3403.5.patch, hive.3403.6.patch, hive.3403.7.patch, hive.3403.8.patch, hive.3403.9.patch
>
>
> Currently, in order to perform a sort merge bucketed join, the user needs
> to set hive.optimize.bucketmapjoin.sortedmerge to true, and also specify the
> mapjoin hint.
> The user should not specify any hints.
--
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