Book Image

Apache Spark 2.x Cookbook

By : Rishi Yadav
Book Image

Apache Spark 2.x Cookbook

By: Rishi Yadav

Overview of this book

While Apache Spark 1.x gained a lot of traction and adoption in the early years, Spark 2.x delivers notable improvements in the areas of API, schema awareness, Performance, Structured Streaming, and simplifying building blocks to build better, faster, smarter, and more accessible big data applications. This book uncovers all these features in the form of structured recipes to analyze and mature large and complex sets of data. Starting with installing and configuring Apache Spark with various cluster managers, you will learn to set up development environments. Further on, you will be introduced to working with RDDs, DataFrames and Datasets to operate on schema aware data, and real-time streaming with various sources such as Twitter Stream and Apache Kafka. You will also work through recipes on machine learning, including supervised learning, unsupervised learning & recommendation engines in Spark. Last but not least, the final few chapters delve deeper into the concepts of graph processing using GraphX, securing your implementations, cluster optimization, and troubleshooting.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Loading and saving data from an arbitrary source


So far, we have covered five data sources that are built-in with DataFrames: Parquet (default), textjson, csv, and jdbc. DataFrames are not limited to these five and can load and save to any arbitrary data source by specifying the format manually.

In this recipe, we will cover the loading and saving of data from arbitrary sources.

How to do it...

  1. Start the Spark shell:
$ spark-shell 
  1. Load the data from Parquet; since parquet is the default data source, you do not have to specify it:
scala> val people = spark.read.load("hdfs://localhost:
          9000/user/hduser/people.parquet") 
  1. Load the data from parquet by manually specifying the format:
scala> val people = spark.read.format("parquet").load
          ("hdfs://localhost:9000/user/hduser/people.parquet") 
  1. For inbuilt datatypes, you do not have to specify the full format name; only specifying "parquet", "json", or "jdbc" would work:
scala> val people = spark.read.format("parquet").load
...