Introduction to database concepts and models

Today, there are several types of database models, but the most common are relational and non-relational models. Relational databases have existed for years and allow you to efficiently manage your data with the ability to perform complex queries and analyses. However, they have certain restrictions, such as the fact that you need to define the database schema (its structure) before you can add data, and changing this later can be difficult. Non-relational databases offer a lot more flexibility and are used for many modern-day web and mobile applications. Let's look at the key differences.

Relational databases

A relational database is often compared to a spreadsheet, although databases offer more capabilities than just letting you analyze data using complex calculations and formulas. Like a spreadsheet, a relational database can be composed of one or more tables. Within each table, you have rows and columns – columns define...