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https://issues.apache.org/jira/browse/HIVE-279?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Prasad Chakka updated HIVE-279:
-------------------------------

    Attachment: hive-279.6.patch

added following tests
1) multi insert (which doesn't push predicates)
2) query containing left and right outer joins

This patch is intended to be committed.

> Implement predicate push down for hive queries
> ----------------------------------------------
>
>                 Key: HIVE-279
>                 URL: https://issues.apache.org/jira/browse/HIVE-279
>             Project: Hadoop Hive
>          Issue Type: New Feature
>          Components: Query Processor
>    Affects Versions: 0.2.0
>            Reporter: Prasad Chakka
>            Assignee: Prasad Chakka
>             Fix For: 0.4.0
>
>         Attachments: hive-279.2.patch, hive-279.3.patch, hive-279.4.patch, 
> hive-279.5.patch, hive-279.6.patch, hive-279.patch
>
>
> Push predicates that are expressed in outer queries into inner queries where 
> possible so that rows will get filtered out sooner.
> eg.
> select a.*, b.* from a join b on (a.uid = b.uid) where a.age = 20 and 
> a.gender = 'm'
> current compiler generates the filter predicate in the reducer after the join 
> so all the rows have to be passed from mapper to reducer. by pushing the 
> filter predicate to the mapper, query performance should improve.

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