[jira] Commented: (HIVE-556) let hive support theta join

["Namit Jain (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HIVE-556?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12718563#action_12718563 ] 

Namit Jain commented on HIVE-556:
---------------------------------

I don't see a use case for this right now. 

The workaround is do a cartesian product (no ON condition) and push the condition in the WHERE clause - the plan will be sub-optimal currently, 
since all data will go to a single reducer.

> let hive support theta join
> ---------------------------
>
>                 Key: HIVE-556
>                 URL: https://issues.apache.org/jira/browse/HIVE-556
>             Project: Hadoop Hive
>          Issue Type: New Feature
>    Affects Versions: 0.4.0
>            Reporter: Min Zhou
>             Fix For: 0.4.0
>
>
> Right now , hive only support equal joins .  Somethings it's not enough, we must consider implementing theta joins like
> {code:sql}
> SELECT
>   a.subid, a.id, t.url
> FROM
>   tbl t JOIN aux_tbl a ON t.url rlike a.url_pattern
> WHERE
>   t.dt='20090609'
>   AND a.dt='20090609';
> {code}
> any condition expression following 'ON' is  appropriate.

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