Question

Point out the wrong statement.

(a) Hadoop has a library package called Aggregate

(b) Aggregate allows you to define a mapper plugin class that is expected to generate “aggregatable items” for each input key/value pair of the mappers

(c) To use Aggregate, simply specify “-mapper aggregate”

(d) None of the mentioned

The question was asked in semester exam.

My question is taken from Hadoop Streaming topic in chapter Mapreduce of Hadoop

Answer 1

Correct option is (c) To use Aggregate, simply specify “-mapper aggregate”

The best I can explain: To use Aggregate, simply specify “-reducer aggregate”