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From Owen O'Malley <omal...@apache.org>
Subject Re: the same key in different reducers
Date Wed, 09 Jun 2010 21:22:43 GMT

On Jun 9, 2010, at 1:17 AM, Oleg Ruchovets wrote:

> So is that case possible or every and every reducer has unique  
> output key?

The partitioner controls which reduce a given key is sent to. If the  
partitioner is non-deterministic, the key can end up going to  
different reduces. If you are using the default hash partitioner, that  
would imply that you didn't define a proper hash code for your key.

-- Owen

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