Big Data Simplified

82 | Big Data Simplied

of reducers, and all results in one partition will go to the corresponding reducer. Thus, all results

from partition 1 will go to the first reducer. Also note that, one particular key is sent to just one

reducer, where the same key cannot be sent to multiple reducers.

Once we have decided that a particular key goes to a particular reducer, then things are exactly

the same as we saw in the case of a single reducer. The pairs are sorted by key such that all values

for the same key occur together in a group, and it is this input that is passed on to the reduce

phase. The reducer will combine all such values with the same ...