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This article mainly explains "how to define MapReduce mapping". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Let the editor take you to learn how to define MapReduce mapping.

Define

Map: commonly known as mapping. The number of elements remains unchanged after map.

Such as:

X-- > (xPhone1)

Y-- > (yPhone1)

Z-- > (zPhone1)

Reduce: commonly known as the specification, the number of elements after reduce (xPhone1)

X-- > (xPhone1)-- > > (xPhone1 / 1 / 1)

X-- > (xPhone1)

MapReduce architecture

Workflow for MR job submission to Yarn = = Yarn architecture design = = Yarn workflow

Shuffle

Map- > shuffle- > reduce

Understanding: the same elements of key are put together through the network IO for business calculation.

Common command

Mapred

At this point, I believe you have a deeper understanding of "how to define MapReduce mapping". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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