crunch-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Chao Shi (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CRUNCH-246) HFileSource
Date Fri, 16 Aug 2013 10:41:50 GMT

    [ https://issues.apache.org/jira/browse/CRUNCH-246?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13742076#comment-13742076
] 

Chao Shi commented on CRUNCH-246:
---------------------------------

Hi Josh, the reason I would prefer PCollection<KeyValue> is that the row-key can be
easily extracted from a KeyValue, so there is no need for this duplication. And also, ImmutableBytesWritable
sounds unnatural to crunch.

One thing I can think of using TableSource is that HBase's HFileOutputFormat does the same.
It does a total-order sort on row-keys. For crunch, I don't think it is necessary (see CRUNCH-212),
as crunch's pipeline is much more flexible. 
                
> HFileSource
> -----------
>
>                 Key: CRUNCH-246
>                 URL: https://issues.apache.org/jira/browse/CRUNCH-246
>             Project: Crunch
>          Issue Type: Improvement
>          Components: IO
>            Reporter: Chao Shi
>            Assignee: Chao Shi
>         Attachments: crunch-246.patch, HFileInputFormat.java
>
>
> I found this useful when directly perform MR on HFiles. I used it yesterday when copying
a bunch of HFiles to another cluster (where the region layout is different).
> There is no HFileInputFormat provided by HBase, but I found the following from google:
> https://gist.github.com/leifwickland/1120311
> http://blog.csdn.net/kirayuan/article/details/7794402 (Java version of the above. The
webpage is in chinese, but you can see the code)
> I'm not sure if we copy their code directly (copyright issue?). Anyone knows?

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Mime
View raw message