hadoop-pig-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Sriranjan Manjunath (JIRA)" <j...@apache.org>
Subject [jira] Updated: (PIG-792) PERFORMANCE: Support skewed join in pig
Date Tue, 28 Jul 2009 18:38:15 GMT

     [ https://issues.apache.org/jira/browse/PIG-792?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Sriranjan Manjunath updated PIG-792:
------------------------------------

    Attachment:     (was: skewedjoin.patch)

> PERFORMANCE: Support skewed join in pig
> ---------------------------------------
>
>                 Key: PIG-792
>                 URL: https://issues.apache.org/jira/browse/PIG-792
>             Project: Pig
>          Issue Type: Improvement
>            Reporter: Sriranjan Manjunath
>         Attachments: skewedjoin.patch
>
>
> Fragmented replicated join has a few limitations:
>  - One of the tables needs to be loaded into memory
>  - Join is limited to two tables
> Skewed join partitions the table and joins the records in the reduce phase. It computes
a histogram of the key space to account for skewing in the input records. Further, it adjusts
the number of reducers depending on the key distribution.
> We need to implement the skewed join in pig.

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


Mime
View raw message