hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Szehon Ho (JIRA)" <>
Subject [jira] [Commented] (HIVE-7384) Research into reduce-side join [Spark Branch]
Date Fri, 22 Aug 2014 21:54:12 GMT


Szehon Ho commented on HIVE-7384:

Did some preliminary research for part2 (parallel reducers), and put findings in HIVE-7856
where the work will happen.

> Research into reduce-side join [Spark Branch]
> ---------------------------------------------
>                 Key: HIVE-7384
>                 URL:
>             Project: Hive
>          Issue Type: Sub-task
>          Components: Spark
>            Reporter: Xuefu Zhang
>            Assignee: Szehon Ho
>         Attachments: Hive on Spark Reduce Side Join.docx, sales_items.txt, sales_products.txt,
> Hive's join operator is very sophisticated, especially for reduce-side join. While we
expect that other types of join, such as map-side join and SMB map-side join, will work out
of the box with our design, there may be some complication in reduce-side join, which extensively
utilizes key tag and shuffle behavior. Our design principle prefers to making Hive implementation
work out of box also, which might requires new functionality from Spark. The tasks is to research
into this area, identifying requirements for Spark community and the work to be done on Hive
to make reduce-side join work.
> A design doc might be needed for this. For more information, please refer to the overall
design doc on wiki.

This message was sent by Atlassian JIRA

View raw message