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Learn Consistency Level in ScyllaDB with Our Console Demo

In previous documentation installments, you’ve learned about ScyllaDB’s ring architecture and you’ve dug into our fault tolerance documentation. Ready to get your hands dirty?  Our consistency level console demo can help you get started immediately.

We’ve used asciinema.org’s sharable terminal sessions to create a series of copyable, pastable command-line console demos to show you what consistency level is in ScyllaDB and how it works in practice.

Consistency Level is a value—configured by the user and tunable per query—which determines how many replicas in a cluster must acknowledge a given read or write operation before it is considered successful.

console demo

So what actually happens during read or write operations when the consistency level is changed and/or nodes are down?

In these demos you’ll observe—with hands-on examples—precisely how to:

  1. Spin up a multiple node cluster using Docker.
  2. Run CQLSH from a Docker container.
  3. Set the consistency level.
  4. Create a keyspace.
  5. Create a table.
  6. Enable tracing.
  7. Trace and understand outputs.
  8. Run a simple table insert to a table.
  9. Run a simple query against a table.
  10. Stop nodes.

You can copy and paste the demo commands for further study and trial. Our demo is intended to illustrate consistency level and what happens on read and write operations when nodes are down.

Like the console demo? Try it out!

Try our console demo here. Click here to learn about our architecture, and see how easy is is to get started with ScyllaDB. Dig into ScyllaDB For Administrators, learn ScyllaDB for Developers, model your own CQL, browse our FAQ and knowledge base and learn how to contribute to ScyllaDB.


Want to give ScyllaDB a try? Explore and try out these very concepts with a download of ScyllaDB or on Docker Hub.  You can also put ScyllaDB through a live performance test.

About ScyllaDB Team

ScyllaDB is the world’s fastest wide-column store database: the functionality of Apache Cassandra with the speed of a light key/value store.