Book Image

Hands-On Big Data Analytics with PySpark

By : Rudy Lai, Bartłomiej Potaczek
Book Image

Hands-On Big Data Analytics with PySpark

By: Rudy Lai, Bartłomiej Potaczek

Overview of this book

Apache Spark is an open source parallel-processing framework that has been around for quite some time now. One of the many uses of Apache Spark is for data analytics applications across clustered computers. In this book, you will not only learn how to use Spark and the Python API to create high-performance analytics with big data, but also discover techniques for testing, immunizing, and parallelizing Spark jobs. You will learn how to source data from all popular data hosting platforms, including HDFS, Hive, JSON, and S3, and deal with large datasets with PySpark to gain practical big data experience. This book will help you work on prototypes on local machines and subsequently go on to handle messy data in production and at scale. This book covers installing and setting up PySpark, RDD operations, big data cleaning and wrangling, and aggregating and summarizing data into useful reports. You will also learn how to implement some practical and proven techniques to improve certain aspects of programming and administration in Apache Spark. By the end of the book, you will be able to build big data analytical solutions using the various PySpark offerings and also optimize them effectively.
Table of Contents (15 chapters)

Actions on key/value pairs

In this section, we'll be looking at the actions on key/value pairs.

We will cover the following topics:

  • Examining actions on key/value pairs
  • Using collect()
  • Examining the output for the key/value RDD

In the first section of this chapter, we covered transformations that are available on key/value pairs. We saw that they are a bit different compared to RDDs. Also, for actions, it is slightly different in terms of result but not in the method name.

Therefore, we'll be using collect() and we'll be examining the output of our action on these key/value pairs.

First, we will create our transactions array and RDD according to userId, as shown in the following example:

 val keysWithValuesList =
Array(
UserTransaction("A", 100),
UserTransaction("B", 4),
UserTransaction("A", 100001),
UserTransaction("B&quot...