Map Reduce program to find the top X
In this recipe, we are going to learn how to write a map reduce program to find the top X records from the given set of values.
Getting ready
To perform this recipe, you should have a running Hadoop cluster as well as an eclipse that's similar to an IDE.
How to do it...
A lot of the time, we might need to find the top X values from the given set of values. A simple example could be to find the top 10 trending topics from a Twitter dataset. In this case, we will need to use two map reduce jobs. First of all, find out all the words that start with # and the number of times each hashtag has occurred in a given set of data. The first map reduce program is quite simple, which is pretty similar to the word count program. ...
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