Introduction
HADOOP MAP REDUCE is a software framework to write application which can process huge amounts of data in-parallel on large clusters. Basically, it’s a programming model for the data processing. Generally, Hadoop can run Map-Reduce Programs Written In Various Languages like Java, Ruby, C++ and Python.
Map reduce works by dividing the processing into two phases
1) Map phase and
2) Reduce phase.
Each phase has the key value pairs as Input and Output, the data types of which can be decided by the programmer. The Map- Reduce program when expressed in code, requires three different things,
1) Map function
2) Reduce function and
3) Code to run the job.
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