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From GUOJUN Zhu <guojun_...@freddiemac.com>
Subject Re: Read key and values from HDFS
Date Fri, 30 Mar 2012 17:26:11 GMT
I believe there is no requirement to save both key and value for the 
OutputFormat, therefore, it is not guaranteed that you can extract 
(key,value) pair from a file generated by an arbitrary OutputFormat. 

Zhu, Guojun
Modeling Sr Graduate
571-3824370
guojun_zhu@freddiemac.com
Financial Engineering
Freddie Mac



   Pedro Costa <psdc1978@gmail.com> 
   03/30/2012 01:19 PM
   Please respond to
mapreduce-user@hadoop.apache.org


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mapreduce-user <mapreduce-user@hadoop.apache.org>
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Subject
Read key and values from HDFS







The ReduceTask can save the file using several output format: 
InternalFileOutputFormant, SequenceFileOutputFormat, TeraOuputFormat, 
etc...

How can I read the keys and the values from the output file? Can anyone 
give me an example? Is there a way to create just one method that can read 
all different outputformat?


Thanks,

-- 
Best regards,


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