You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@pig.apache.org by "Olga Natkovich (JIRA)" <ji...@apache.org> on 2011/03/17 19:38:29 UTC
[jira] Updated: (PIG-1322) Logical Optimizer: change outer join
into regular join
[ https://issues.apache.org/jira/browse/PIG-1322?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Olga Natkovich updated PIG-1322:
--------------------------------
Fix Version/s: (was: 0.9.0)
> Logical Optimizer: change outer join into regular join
> ------------------------------------------------------
>
> Key: PIG-1322
> URL: https://issues.apache.org/jira/browse/PIG-1322
> Project: Pig
> Issue Type: Sub-task
> Components: impl
> Affects Versions: 0.7.0
> Reporter: Daniel Dai
> Assignee: Xuefu Zhang
>
> In some cases, we can change the outer join into a regular join. The benefit is regular join is easier to optimize in subsequent optimization.
> Example:
> C = join A by a0 LEFT OUTER, B by b0;
> D = filter C by b0 > 0;
> =>
> C = join A by a0, B by b0;
> D = filter C by b0 > 0;
> Because we made this change, so PushUpFilter rule can further push the filter in front of regular join which otherwise cannot.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira