This document discusses using Apache Spark and Cassandra together for real-time analytics on transactional data. It provides an overview of Cassandra and how it can be used for operational applications like recommendations, fraud detection, and messaging. It then discusses how the Spark Cassandra Connector allows reading and writing Cassandra data from Spark, enabling real-time analytics on streaming and batch data using Spark SQL, MLlib, and Spark Streaming. It also covers some DataStax Enterprise features for high availability and integration of Spark and Cassandra.