hadoop-pig-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Olga Natkovich (JIRA)" <j...@apache.org>
Subject [jira] Assigned: (PIG-361) JOIN and cogroup should handle NULLs correctly
Date Thu, 04 Sep 2008 01:09:44 GMT

     [ https://issues.apache.org/jira/browse/PIG-361?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Olga Natkovich reassigned PIG-361:
----------------------------------

    Assignee: Shravan Matthur Narayanamurthy  (was: Alan Gates)

Shravan, could you take a look plaese. 

I think we want to preserve SQL semantics here:

JOIN / INNER COGROUP - throws away all NULLs
OUTER COGROUP + flatten with bincond  simulates outer joins where missing data is padded by
NULLs and  nulls are assumed to be all different - never multiplied.

> JOIN and cogroup should handle NULLs correctly
> ----------------------------------------------
>
>                 Key: PIG-361
>                 URL: https://issues.apache.org/jira/browse/PIG-361
>             Project: Pig
>          Issue Type: Sub-task
>    Affects Versions: types_branch
>            Reporter: Pradeep Kamath
>            Assignee: Shravan Matthur Narayanamurthy
>             Fix For: types_branch
>
>
> JOIN should follow SQL semantics .i.e if the join key is a null or part of the join key
is null in the first table, it should not join with similar keys in the second table.
> Cogroup should coalesce all NULL key rows into one group.

-- 
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