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From "Xuefu Zhang (JIRA)" <j...@apache.org>
Subject [jira] [Comment Edited] (HIVE-8017) Use HiveKey instead of BytesWritable as key type of the pair RDD [Spark Branch]
Date Tue, 09 Sep 2014 16:18:28 GMT

    [ https://issues.apache.org/jira/browse/HIVE-8017?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14127157#comment-14127157
] 

Xuefu Zhang edited comment on HIVE-8017 at 9/9/14 4:17 PM:
-----------------------------------------------------------

Hi Rui,

{quote}
Have you try – SORT_BEFORE_DIFF, which is to sort the query result, which is different from
SORT_BEFORE_DIFF. It's supposed to make query result sorted w/o an order by.
{quote}

This comment indeeded made no sense. Sorry for the confusion, I meant "-- SORT_QUERY_RESULTS"
for the first "-- SORT_BEFORE_DIFF". So my comment should really go like this:

{quote}
Have you tried – SORT_QUERY_RESULTS, which is to sort the query result, which is different
from SORT_BEFORE_DIFF. It's supposed to make query result sorted w/o an order by.
{quote}

 SORT_BEFORE_DIFF sorts the output files before making diff. It's less reliable, and sometimes
the diff doesn't tell what's wrong. Thus, I think we should prefer SORT_QUERY_RESULTS when
query output can diff in order. 

Neither do I know why SORT_BEFORE_DIFF has to come after set commands in your case, but it
seems the usage of it in the .q files is not consistent on that front.



was (Author: xuefuz):
Hi Rui,

{quote}
Have you tried – SORT_BEFORE_DIFF, which is to sort the query result, which is different
from SORT_BEFORE_DIFF. It's supposed to make query result sorted w/o an order by.
{quote}

This comment indeeded made no sense. Sorry for the confusion, I meant "-- SORT_QUERY_RESULTS"
for the first "-- SORT_BEFORE_DIFF". So my comment should really go like this:

{bold}
Have you tried – SORT_QUERY_RESULTS, which is to sort the query result, which is different
from SORT_BEFORE_DIFF. It's supposed to make query result sorted w/o an order by.
{bold}

 SORT_BEFORE_DIFF sorts the output files before making diff. It's less reliable, and sometimes
the diff doesn't tell what's wrong. Thus, I think we should prefer SORT_QUERY_RESULTS when
query output can diff in order. 

Neither do I know why SORT_BEFORE_DIFF has to come after set commands in your case, but it
seems the usage of it in the .q files is not consistent on that front.


> Use HiveKey instead of BytesWritable as key type of the pair RDD [Spark Branch]
> -------------------------------------------------------------------------------
>
>                 Key: HIVE-8017
>                 URL: https://issues.apache.org/jira/browse/HIVE-8017
>             Project: Hive
>          Issue Type: Sub-task
>          Components: Spark
>            Reporter: Rui Li
>            Assignee: Rui Li
>         Attachments: HIVE-8017-spark.patch, HIVE-8017.2-spark.patch
>
>
> HiveKey should be used as the key type because it holds the hash code for partitioning.
While BytesWritable serves partitioning well for simple cases, we have to use {{HiveKey.hashCode}}
for more complicated ones, e.g. join, bucketed table, etc.



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