Book Image

Learning Apache Flink

By : Tanmay Deshpande
Book Image

Learning Apache Flink

By: Tanmay Deshpande

Overview of this book

<p>With the advent of massive computer systems, organizations in different domains generate large amounts of data on a real-time basis. The latest entrant to big data processing, Apache Flink, is designed to process continuous streams of data at a lightning fast pace.</p> <p>This book will be your definitive guide to batch and stream data processing with Apache Flink. The book begins with introducing the Apache Flink ecosystem, setting it up and using the DataSet and DataStream API for processing batch and streaming datasets. Bringing the power of SQL to Flink, this book will then explore the Table API for querying and manipulating data. In the latter half of the book, readers will get to learn the remaining ecosystem of Apache Flink to achieve complex tasks such as event processing, machine learning, and graph processing. The final part of the book would consist of topics such as scaling Flink solutions, performance optimization and integrating Flink with other tools such as ElasticSearch.</p> <p>Whether you want to dive deeper into Apache Flink, or want to investigate how to get more out of this powerful technology, you’ll find everything you need inside.</p>
Table of Contents (17 chapters)
Learning Apache Flink
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Iterations


One of the unique features Flink supports is iterations. These days a lot developers want to run iterative machine-learning and graph-processing algorithms using big data technologies. To cater to these needs, Flink supports running iterative data processing by defining a step function.

Iterator operator

An iterator operator consists of the following components:

  • Iteration Input: This is either the initial dataset received or the output of the previous iteration

  • Step Function: This is the function that needs to be applied on input dataset

  • Next Partial Solution: This is the output of the step function which needs to be fed back to the next iteration

  • Iteration Result: After all iterations are completed, we get the result of iterations

The number of iterations can be controlled by various ways. One way could be setting up the number of iterations to perform or we can also put conditional termination.

Delta iterator

The delta operator iterates over the set of elements for incremental iteration...