Book Image

Big Data Analytics

By : Venkat Ankam
Book Image

Big Data Analytics

By: Venkat Ankam

Overview of this book

Big Data Analytics book aims at providing the fundamentals of Apache Spark and Hadoop. All Spark components – Spark Core, Spark SQL, DataFrames, Data sets, Conventional Streaming, Structured Streaming, MLlib, Graphx and Hadoop core components – HDFS, MapReduce and Yarn are explored in greater depth with implementation examples on Spark + Hadoop clusters. It is moving away from MapReduce to Spark. So, advantages of Spark over MapReduce are explained at great depth to reap benefits of in-memory speeds. DataFrames API, Data Sources API and new Data set API are explained for building Big Data analytical applications. Real-time data analytics using Spark Streaming with Apache Kafka and HBase is covered to help building streaming applications. New Structured streaming concept is explained with an IOT (Internet of Things) use case. Machine learning techniques are covered using MLLib, ML Pipelines and SparkR and Graph Analytics are covered with GraphX and GraphFrames components of Spark. Readers will also get an opportunity to get started with web based notebooks such as Jupyter, Apache Zeppelin and data flow tool Apache NiFi to analyze and visualize data.
Table of Contents (18 chapters)
Big Data Analytics
Credits
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Evolution of DataFrames and Datasets


A DataFrame is used for creating rows and columns of data just like a Relational Database Management System (RDBMS) table. DataFrames are a common data analytics abstraction that was introduced in the R statistical language and then introduced in Python with the proliferation of the Pandas library and the pydata ecosystem. DataFrames provide easy ways to develop applications and higher developer productivity.

Spark SQL DataFrame has richer optimizations under the hood than R or Python DataFrame. They can be created from files, pandas DataFrames, tables in Hive, external databases like MySQL, or RDDs. The DataFrame API is available in Scala, Java, Python, and R.

While DataFrames provided relational operations and higher performance, they lacked type-safety, which led to run-time errors. While it is possible to convert a DataFrame to a Dataset, it required a fair amount of boilerplate code and it was expensive. So, the Dataset API is introduced in version...