Working with NoSQL databases
In the previous section of this chapter, you learned the basics of relational databases and how to use SQL to query data. Relational data is mostly organized in a tabular form, that is, as a collection of tables with relations.
However, when the volume of data exceeds the capacity of a server, problems occur because the traditional model of relational databases does not easily support horizontal scalability, that is, storing data in a cluster of servers instead of a single one. This adds a new layer of complexibility of database management as the data is stored in a distributed form while still accessible as one logical database.
In recent years, NoSQL, or non-relational databases, have become much more popular than before due to the introduction of new database models and the remarkable performance they exhibit in big data analytics and real-time applications. Some non-relational databases are designed for high availability, scalability, and flexibility...