Hey everyone. I have a doubt in mapreduce. In mapreduce each reduce task write its output to a file named part-r-nnnnn where nnnnn is a partition ID associated with the reduce task. Does map/reduce merge these files? If yes, how?
Hey there, instead of doing the file merging on your own, you can delegate the entire merging of the reduce output files by calling:
hadoop fs -getmerge /output/dir/on/hdfs/ /desired/local/output/file.txt
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org.apache.hadoop.mapreduce is the ...READ MORE
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