Mastering Flask Web Development - Second Edition

The strengths of NoSQL databases

The main reason that many people use NoSQL databases is its speed advantage over traditional databases. Out of the box, many NoSQL databases can outperform RDBMSes. However, a well-tuned and properly scaled SQL database with read slaves can outperform NoSQL databases. Many NoSQL databases, especially document stores, sacrifice consistency for availability. This means that they can handle many concurrent reads and writes, but those writes may be in conflict with one another. Yet, this is not straightforward, as you will soon see when we look at the CAP theorem.

The second feature that pulls people to NoSQL is its ability to handle unformatted data. Storing data in XML or JSON allows an arbitrary structure to ...