[
https://issues.apache.org/jira/browse/HIVE-11152?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14609381#comment-14609381
]
Laljo John Pullokkaran commented on HIVE-11152:
-----------------------------------------------
[~jcamachorodriguez]
1.
Add a comment to plan modifier why are we adding project only if right is a
join and left is not a join (about swapping left and right). This is little bit
of a hack in the sense that swapping is done by ASTConverter. Swapping should
be done by PlanModifier instead as it is its purpose.
This should be done in a separate pass in planmodifier(or keep track of joins
that need this swap).
2. With #1 changes in ASTConverter will be migrated to PlanModifier.
> Swapping join inputs in ASTConverter
> ------------------------------------
>
> Key: HIVE-11152
> URL: https://issues.apache.org/jira/browse/HIVE-11152
> Project: Hive
> Issue Type: Bug
> Components: CBO
> Reporter: Jesus Camacho Rodriguez
> Assignee: Jesus Camacho Rodriguez
> Attachments: HIVE-11152.patch
>
>
> We want that multijoin optimization in SemanticAnalyzer always kicks in when
> CBO is enabled (if possible). For that, we may need to swap the join inputs
> when we return from CBO through the Hive AST.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
