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From Rares Vernica <rvern...@gmail.com>
Subject get number of values for a key
Date Sat, 13 Jun 2009 22:40:54 GMT

In Reduce, can I get the number of values for the current key without
iterating over them? Does Hadoop has this number?

Or, at least the total number of pairs that will be processed by the
current Reduce instance. I am pretty sure that Hadoop already knows
this number because it sorted them.

BTW, the iterators given to Reduce are one-time use iterators, right?


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