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

Data sinks


After the data transformations are done, we need to save results into some place. The following are some options Flink provides us to save results:

  • writeAsText(): Writes records one line at a time as strings.

  • writeAsCsV(): Writes tuples as comma separated value files. Row and fields delimiter can also be configured.

  • print()/printErr(): Writes records to the standard output. You can also choose to write to the standard error.

  • writeUsingOutputFormat(): You can also choose to provide a custom output format. While defining the custom format you need to extend the OutputFormat which takes care of serialization and deserialization.

  • writeToSocket(): Flink supports writing data to a specific socket as well. It is required to define SerializationSchema for proper serialization and formatting.