Describe how you would implement a MapReduce job consisting of Map and Reduce description for the specific query. Just describe, in your own words, what the Map and Reduce tasks are going to do in the specific query a. Map task reads the input file and produces (key, value) pairs. Reduce task takes a list of (key, value) pairs for each key and combines all values for each key. Please remember that Map operates on individual blocks and Reduce on individual keys with a set of values. Thus, for Mapper you need to state what your code does given a block of data (i.e., for each block, not for the whole file) and for Reduce you need to state what your reducer does for each key (without being able to see other key). Broad answers that do related the the specific query below will not receive any credit.

a)

SELECT d_month, COUNT(d_sellingseason)

FROM dwdate

GROUP BY d_month

ORDER BY COUNT(d_sellingseason);