Book Image

Scala and Spark for Big Data Analytics

By : Md. Rezaul Karim, Sridhar Alla
Book Image

Scala and Spark for Big Data Analytics

By: Md. Rezaul Karim, Sridhar Alla

Overview of this book

Scala has been observing wide adoption over the past few years, especially in the field of data science and analytics. Spark, built on Scala, has gained a lot of recognition and is being used widely in productions. Thus, if you want to leverage the power of Scala and Spark to make sense of big data, this book is for you. The first part introduces you to Scala, helping you understand the object-oriented and functional programming concepts needed for Spark application development. It then moves on to Spark to cover the basic abstractions using RDD and DataFrame. This will help you develop scalable and fault-tolerant streaming applications by analyzing structured and unstructured data using SparkSQL, GraphX, and Spark structured streaming. Finally, the book moves on to some advanced topics, such as monitoring, configuration, debugging, testing, and deployment. You will also learn how to develop Spark applications using SparkR and PySpark APIs, interactive data analytics using Zeppelin, and in-memory data processing with Alluxio. By the end of this book, you will have a thorough understanding of Spark, and you will be able to perform full-stack data analytics with a feel that no amount of data is too big.
Table of Contents (19 chapters)

Stateful/stateless transformations

As seen previously, Spark Streaming uses a concept of DStreams, which are essentially micro-batches of data created as RDDs. We also saw types of transformations that are possible on DStreams. The transformations on DStreams can be grouped into two types: Stateless transformations and Stateful transformations.

In Stateless transformations, the processing of each micro-batch of data does not depend on the previous batches of data. Thus, this is a stateless transformation, with each batch doing its own processing independently of anything that occurred prior to this batch.

In Stateful transformations, the processing of each micro-batch of data depends on the previous batches of data either fully or partially. Thus, this is a stateful transformation, with each batch considering what happened prior to this batch and then using the information while...