In this chapter, we learned about different storage engines in MongoDB. We identified the pros and cons of each one and the use cases for choosing each storage engine.

We learned about using multiple storage engines, how we can use them, and the benefits.

A big part of this chapter was also dedicated to database locking, how it can happen, why it is bad, and how we can avoid it.

We split our operations by the lock they need. This way, when we design and implement our application, we can make sure that we have a design that locks our database as little as possible.

In the next chapter, we will learn about MongoDB and how we can use it to ingest and process big data.