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)

Leveraging JSON as a data format

In this section, we will leverage JSON as a data format and save our data in JSON. The following topics will be covered:

  • Saving data in JSON format
  • Loading JSON data
  • Testing

This data is human-readable and gives us more meaning than simple plain text because it carries some schema information, such as a field name. We will then learn how to save data in JSON format and load our JSON data.

We will first create a DataFrame of UserTransaction("a", 100) and UserTransaction("b", 200), and use .toDF() to save the DataFrame API:

val rdd = spark.sparkContext
.makeRDD(List(UserTransaction("a", 100), UserTransaction("b", 200)))
.toDF()

We will then issue coalesce() and, this time, we will take the value as 2, and we will have two resulting files. We will then issue the write.format method and, for...