Learn About the Recent Cassandra 4.0 Release with a New Online Course from DataStax

If you’re ready to dive into Apache Cassandra 4.0®, you need to check out the new online learning series, “What’s New in Cassandra 4.0?” developed by DataStax. This course will help you get up to speed fast with nine modules describing all the new features in this release complete with hands-on training exercises to help you understand and learn how to use them.

We’ve waited six years for the release of Cassandra 4.0. In that time, a lot of progress has been made toward making Cassandra the highest performing database available today. With many new features and more than 1,000 bug fixes, Cassandra 4.0 comes loaded and is now faster and more scalable than ever.

At DataStax we’ve put together a series of Cassandra 4.0 lessons describing What’s New as well as including a number of interactive, hands-on exercises to help you learn how to use many of the new features. You’ll be hearing from the best with videos created by the engineers who developed the learning experience.

In this series, you’ll learn:

  • How to use virtual tables and the different commands you can use with them.
  • How to enable and configure audit logging.
  • How to improve communications between nodes with async internode messaging.
  • How to use Cassandra’s new database repair and improvement tools.
  • How to use some of the new, experimental features in Cassandra 4.0 to reduce the amount of storage required to achieve more consistency and in your database.
  • How to see the exact CQL queries used so you can troubleshoot queries that are performing poorly or not producing the right results.
  • How zero-copy streaming can help you avoid downtime with rapid replacement or build.

Introduction to Apache Cassandra 4.0

If you need any persuading to start using Cassandra 4.0 then this module is for you. We offer an overview of all the new features and improvements that will make your applications run faster and more efficiently.

We’ll also cover the changes in Cassandra 4.0 that make it easier to use and how you can migrate from older versions following a few simple steps.

Virtual Tables

Virtual tables give you the power to access the status of your database components and the relevant metrics describing them. Virtual tables eliminate the need to use the Java Management Extension (JMX) framework, giving you read access without the burden of configuration.

We’ve put together an interactive learning environment that will give you the opportunity to get hands-on experience executing commands on virtual tables. Within this environment, you can see firsthand what virtual tables look like and give you a good understanding of their current limitations.

Audit Logging

If you’re interested in learning how to work with a truly enterprise-level database, the kind that manages huge datasets accessed by hundreds (if not thousands) of people at any given time, developing an understanding of audit logging is a must.

In order to comply with regulations such as SOX, PCI, and GDPR, you need audit logging to see who is accessing what data, which helps to limit the chance of a data breach and to protect the privacy of users.

In this lesson, you’ll learn how to enable audit logging, see which fields can be logged, and learn how to configure various settings using the interactive learning environment.

Async Internode Messaging

With the increased adoption of the Netty Transport Framework through Cassandra’s codebase, you will see an improvement in communications between nodes. The network infrastructure has been improved, making scaling nodes easier and faster and the time to recover nodes has been reduced.

This feature is one of the most significant advancements to Cassandra because it can have a huge impact on the performance of your applications.

This module will show you how communication between nodes is more efficient and reliable as a result of changes in receiving messages, how technical debt has been cleaned up, and how you can view internode metrics via virtual tables in Cassandra 4.0.

Migration Guide

If you aren’t using Cassandra 4.0 yet, now is the time to start planning. If you’re already using Cassandra, you’ll want to prepare to migrate your 3.x version to enjoy all the benefits the 4.0 provides.

This module will help you in either case. By following a few simple steps, you will see how easy it is to migrate from 3.x to 4.0 and how to verify that your nodes have been upgraded.

Repair and Improvement Tools

In Cassandra, entropy occurs. This is when the replicas slowly drift away from each other, causing differences in data. This can happen from file corruption, nodes going down, or network failures.

Cassandra has tools to help to maintain your database and keep data consistent across nodes. One of these tools is incremental repair, which was first released in 2.1. With the release of 4.0, incremental repair offers many new improvements.

In this module, we’ll cover these new improvements, including improved transaction between nodes, advancements in anti-compaction performance, and help with problems of over streaming, all of which will help you more easily maintain the integrity of your database.

Experimental Features

Sometimes the Cassandra community creates new and exciting features which can have a critical impact on certain areas in the database. To allow users the ability to test and provide feedback on newly developed features that have not yet been proven to be battle-hardened and stable, Cassandra allows the user an option to enable or disable these experimental features as needed.

Two new experimental features added in 4.0 are transient replication and support for Java Development Kit (JDK) 11.

Transient replication was created to help reduce the amount of storage allowing you to achieve your desired level of consistency. This is done by creating transient replicas which only retain replicated data until it can be propagated to full replicas, via incremental repair, at which point the data is deleted.

Cassandra 4.0 has experimental support for JDK 11, which allows users to access new garbage collection algorithms such as ZGC and Shenandoah, which can provide more consistent, predictable latencies for your Cassandra queries.

In this module, you’ll learn how transient replication works and how it reduces the amount of storage needed. We’ll also introduce you to the promise that JDK 11 offers when it comes to garbage collection.

Full Query Logging

Full query logging (FQL) is similar to audit logging, but FQL logs all successful Cassandra query language (CQL) requests; ones that modify data and those that just query.

With FQL, you can monitor live traffic as well as examine existing activity. This is extremely helpful to debug queries that you find are producing unexpected results or if you want to test or audit CQL queries.

This module will show you how to enable and disable FQL, how to view the logs, and what properties are configurable.

Zero Copy Streaming

Zero Copy Streaming is an approach to data transfer in which the data is streamed directly from the disk file as opposed to going through the application, which improves application performance.

In previous versions of Cassandra, during streaming, the sorted strings tables (SSTables) are always reified into objects. This method of streaming implies unnecessary operations and slows down the whole transfer process because some SSTables can be transferred as a whole file rather than individual partitions.

Cassandra 4.0 now offers support for streaming entire SSTables whenever possible (CASSANDRA-14556) to provide faster streaming using ZeroCopy APIs. When enabled, Cassandra will use ZeroCopy for eligible SSTables to significantly speed up transfers and increase throughput.

With zero-copy streaming in Cassandra 4.0, you can now:

  • Decrease costs of data transfer (less CPU/RAM intensive operations)
  • Scale-out or scale in your cluster faster (shorter bootstrapping/decommissioning time)
  • Build a more dynamic infrastructure
  • Avoid potential downtime resulting from a failed node with the ability to replace or rebuild it on the fly

In this module, you’ll learn more about these benefits, how zero-copy streaming in Cassandra 4.0 works, and what you might want to change in the configuration given your use case.

Cassandra 4.0 is packed with lots of new features that will make improvements to your database. This three-hour course, developed and presented by DataStax Cassandra experts, will show you all the new features in 4.0 so you see which improvements are the most important. (We may be a bit biased, but we think they’re all great!) So, head over to the course page and start learning now. No registration is required!

Follow the DataStax Tech Blog for more developer stories. Check out our YouTube channel for tutorials and here for DataStax Developers on Twitter for the latest news about our developer community.


  1. DataStax Free Online Learning Series: What’s New in Cassandra 4.0?
  2. Cassandra 4.0 Press Release
  3. New Features in Apache Cassandra 4.0
  4. Streaming Entire SSTables When Possible in Cassandra
  5. Cassandra Documentation: Virtual Tables
  6. Cassandra Documentation: Audit Logging
  7. Cassandra Documentation: Improved Internode Messaging
  8. Cassandra Documentation: Full Query Logging
  9. Cassandra Documentation: Zero Copy Streaming
  10. Efficient Data Transfer Through Zero Copy
  11. The Cassandra Query Language (CQL)
  12. Understanding the JDK’s New Superfast Garbage Collectors
  13. Join our Discord: Fellowship of the (Cassandra) Rings
  14. Astra DB — Managed Apache Cassandra as a Service
  15. Getting started with GraphQL and Apache Cassandra
  16. Stargate APIs | GraphQL, REST, Document
  17. DataStax Academy
  18. DataStax Certifications
  19. DataStax Workshops



Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store

DataStax is the company behind the massively scalable, highly available, cloud-native NoSQL data platform built on Apache Cassandra®.