hadoop-pig-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Alan Gates (JIRA)" <j...@apache.org>
Subject [jira] Commented: (PIG-51) Combiner gives wrong result in the presence of flattening
Date Thu, 13 Dec 2007 17:57:43 GMT

    [ https://issues.apache.org/jira/browse/PIG-51?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12551565
] 

Alan Gates commented on PIG-51:
-------------------------------

+1, patch looks good.

> Combiner gives wrong result in the presence of flattening
> ---------------------------------------------------------
>
>                 Key: PIG-51
>                 URL: https://issues.apache.org/jira/browse/PIG-51
>             Project: Pig
>          Issue Type: Bug
>            Reporter: Utkarsh Srivastava
>            Priority: Critical
>         Attachments: combiner-flatten.patch
>
>
> If you do something like
> a = load ... as (f1,f2,f3);
> b = group a by (f1,f2);
> c = foreach b generate flatten(group), SUM(a.f3);
> The reduce side refers to field number expecting data will not have been flattened yet.
But if the combiner kicks in, it already flattens the group, leading to column references
being wrong.
>  

-- 
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