From https://blog.pythian.com/cassandra-use-cases/

“Ideal Cassandra Use Cases It turns out that Cassandra is really very good for some applications. The ideal Cassandra application has the following characteristics: * Writes exceed reads by a large margin. * Data is rarely updated and when updates are made they are idempotent. * Read Access is by a known primary key. * Data can be partitioned via a key that allows the database to be spread evenly across multiple nodes. * There is no need for joins or aggregates. Some of my favorite examples of good use cases for Cassandra are: * Transaction logging: Purchases, test scores, movies watched and movie latest location. * Storing time series data (as long as you do your own aggregates). * Tracking pretty much anything including order status, packages etc. * Storing health tracker data. * Weather service history. * Internet of things status and event history. * Telematics: IOT for cars and trucks. * Email envelopes—not the contents.”