What is a non-relational database?
A non-relational database, also known as NoSQL database, offers an alternative model to a traditional relational database, whereby you can store, retrieve, and link data. In a relational database, your data is stored in tables and rows, linked by keys, whereas non relational databases come in many different forms of models, and are typically used for fluctuating data sets and requirements, making them perfect for handling big data and real-time applications.
Big data grows rapidly, changes a lot (and changes quickly), and has a diversified structure. Relational database models were not designed with these requirements in mind, so are inefficient at storing, retrieving, and linking this data. On the other hand, the right type of non-relational database can store and manage data with great flexibility, perform high speed operations and scale easily, making it a clear choice for developers in these sort of applications.
The differences between NoSQL and relational databases really depend on your data set and applications.