JavaScript (Node.js) and Databases: A Practical Guide

The book "JavaScript (Node.js) and Databases: A Practical Guide" is a comprehensive navigator through the world of data storage and processing for backend developers using Node.js. The author, Alexey Sokolov, a senior developer with 10 years of experience, has gathered under one cover everything needed for confident work with relational and document-oriented databases.

What is this book about?

You will start with the basics: installing drivers, configuring connections, and working with connection pools. Then you will dive into writing queries — from simple SELECT to complex JOINs and aggregations. Dedicated chapters cover:

• Working with PostgreSQL via the pg library and with MongoDB via mongoose;
• ORM systems (Sequelize, TypeORM, Prisma) — when they are useful and when it is better to write plain SQL;
• Database migrations and seeding;
• Performance optimization: indexes, explain, caching;
• Security: protection against SQL injection, data validation, transactions;
• Working with Redis as a cache and message broker.

Who is this book for?

• Beginning JavaScript developers who want to master backend development with Node.js;
• Backend developers transitioning from other languages (Python, PHP, Java) to Node.js;
• Fullstack developers looking to deepen their knowledge of working with data;
• Students and anyone preparing for a Node.js developer interview.

What will you learn after reading?

• How to design a database schema for specific tasks;
• How to write efficient and secure queries using asynchronous patterns;
• How to configure a connection pool and avoid memory leaks;
• How to integrate multiple DBMS in one project (PostgreSQL + MongoDB + Redis);
• How to automate migrations and manage schema versions;
• How to test code that works with a database using Jest and Docker.

All code examples are available for download and come with detailed comments. The book is built on the principle of "from simple to complex": each chapter contains a theoretical part, practical assignments, and an analysis of typical mistakes. This is not just a reference book, but a real guide to action that will help you write reliable and scalable backend code in Node.js.