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Question about combiners

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Question about combiners

New Contributor

Is a combiner always defined in terms of a reducer or is there another way to code the combiner class?

 

Thanks in advance to all who answer.

Thanks in advance to all who reply.

Kevin
1 ACCEPTED SOLUTION

Accepted Solutions

Re: Question about combiners

Like the definitive guide says "Hadoop allows the user to specify a
combiner function to be run on the map output, and the combiner function’s
output forms the input to the reduce function. "
​. Frequently the code in the reducer and combiner is similar but doesn't
have to be. ​


Your question is unclear.
​ Can you elaborate a bit?


Regards,
Gautam Gopalakrishnan
2 REPLIES 2

Re: Question about combiners

Like the definitive guide says "Hadoop allows the user to specify a
combiner function to be run on the map output, and the combiner function’s
output forms the input to the reduce function. "
​. Frequently the code in the reducer and combiner is similar but doesn't
have to be. ​


Your question is unclear.
​ Can you elaborate a bit?


Regards,
Gautam Gopalakrishnan

Re: Question about combiners

New Contributor

Thanks, your answer was fine.

Thanks in advance to all who reply.

Kevin