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From dealmaker <vin...@gmail.com>
Subject Can I have Reducer with No Output?
Date Thu, 28 May 2009 07:57:21 GMT

Hi,
  I have maps that do most of the work, and they output the data into a
reducer, so basically key is a constant, and the reducer combines all the
input from maps into a file and it does "LOAD_DATA" the file into mysql db. 
So, there won't be any output.collect ( ) in reducer function.  But when I
write the class Reducer, the compiler keeps complaining about the missing 2
types at the end of in "private static class Reducer extends MapReduceBase
implements Reducer<Text, Writable> " which doesn't have output.collect ( ). 
What should I put in there?

Do I even need Reducer at all?  I think that only one reducer saves the file
will be more efficient, rather than having all the map to save data into
same file individually.  Any better way to do this?

Thanks.
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