Databases

Databases are the backbone of nearly every application you use — from social media feeds and online stores to banking systems and search engines. A database is an organized collection of data that can be efficiently stored, retrieved, and managed. Understanding databases is a fundamental skill for any developer.

Types of Databases

Databases generally fall into two broad categories:

• Relational Databases (SQL): Store data in structured tables with rows and columns, linked by relationships. Examples include PostgreSQL, MySQL, and SQLite. They use SQL (Structured Query Language) to define and manipulate data, and enforce strict schemas to maintain data integrity.
• NoSQL Databases: Designed for flexibility and scale, NoSQL databases store data in formats like documents, key-value pairs, graphs, or wide columns. Examples include MongoDB, Redis, and DynamoDB. They’re often chosen when data structures are varied or when horizontal scaling is a priority.

Why Learn Databases?

Almost every software application needs to persist data. Whether you’re building a web app, a mobile app, or a data pipeline, you’ll interact with a database. Understanding how databases work — how to design schemas, write efficient queries, and choose the right database for the job — makes you a more effective developer.

What You’ll Learn

In this series, we’ll start with the fundamentals of SQL and relational databases, then explore NoSQL options like MongoDB and Redis. You’ll learn how to create tables, query data, optimize performance, and make informed decisions about which database fits your use case.

See the tutorials below to get started.