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From Joey Echeverria <j...@cloudera.com>
Subject Re: Are the input values (associated with a specific key) of reduce() method sorted?
Date Tue, 06 Dec 2011 01:36:13 GMT
Hi James,

By default, there is no guarantees on value order. Using some of the
more advanced API features, you can perform a secondary sort of
values. You can read a good example of it here:

http://sonerbalkir.blogspot.com/2010/01/simulating-secondary-sort-on-values.html

-Joey

On Mon, Dec 5, 2011 at 7:55 PM, James Y. Li <yueli.m@gmail.com> wrote:
> Hi All,
> I just begin to use Hadoop framework, and write my reduce() method. Wonder
> if the Iterable input values (associated with the input key) are already
> sorted. Thanks!
>
> p.s. I am using the version 0.20.2-cdh3u1
>
> -james
>
> --
>
>



-- 
Joseph Echeverria
Cloudera, Inc.
443.305.9434

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