Book Image

Learning Apache Cassandra - Second Edition

Book Image

Learning Apache Cassandra - Second Edition

Overview of this book

Cassandra is a distributed database that stands out thanks to its robust feature set and intuitive interface, while providing high availability and scalability of a distributed data store. This book will introduce you to the rich feature set offered by Cassandra, and empower you to create and manage a highly scalable, performant and fault-tolerant database layer. The book starts by explaining the new features implemented in Cassandra 3.x and get you set up with Cassandra. Then you’ll walk through data modeling in Cassandra and the rich feature set available to design a flexible schema. Next you’ll learn to create tables with composite partition keys, collections and user-defined types and get to know different methods to avoid denormalization of data. You will then proceed to create user-defined functions and aggregates in Cassandra. Then, you will set up a multi node cluster and see how the dynamics of Cassandra change with it. Finally, you will implement some application-level optimizations using a Java client. By the end of this book, you'll be fully equipped to build powerful, scalable Cassandra database layers for your applications.
Table of Contents (14 chapters)

Chapter 13. Peeking under the Hood

Over the previous 12 chapters, we've thoroughly explored Cassandra's capabilities from the perspective of application developers. All of our interaction with Cassandra has been through CQL, and we've explored a robust set of features available to us via the CQL interface. We've found that one of the big appeals of Cassandra is the rich set of data structures available to us for domain modeling; structures such as compound primary keys, collection columns, and secondary indexes are part of  what sets Cassandra apart from other distributed databases.

As it turns out, CQL is an abstraction on top of a much less sophisticated data structure that underlies all the data stored in Cassandra. Commonly referred to as the Thrift interface, named after the protocol used to interact with Cassandra at this level, this layer represents all data using an ad hoc key-value structure called a column family. As developers, we will never need to interact with Cassandra at this...