In this chapter, we learned about CQL as a mechanism to insert and retrieve data out of Cassandra. We also talked about how a secondary index will help in searching for the data when the primary key is not known. In the following chapters, we will talk a little more on the internals of Cassandra.

In the next chapter, we will cover more on performance tuning based on the application's data model and usage. Having a better understanding of how the system works will help us understand Cassandra's performance profiles.