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 4. Beyond Key-Value Lookup

In the last chapter, we explored a powerful data organization concept in Cassandra - the compound primary key. This allowed us to construct a table for status updates that satisfies two important requirements: related data is grouped together, and records have a built-in ordering within each group. So far, however, we only have two tools for querying data: either retrieve a single row using its full primary key, or retrieve all the rows in a table. In this chapter, we will dive into the more sophisticated queries that are available on tables with clustering columns, and use these queries to build the main reading interface for our MyStatus application. By the end of this chapter, you'll know:

  • How to retrieve all rows within a single partition
  • How to retrieve rows within a range of clustering column values
  • How to paginate over rows in a single partition
  • How to change the order of results
  • How to store rows in descending order of clustering column
  • How to paginate...