This book, Mastering MongoDB 4.x, provides an in-depth exploration of MongoDB's features and capabilities, empowering readers to create high-performance and fault-tolerant database solutions. Through practical examples and clear explanations, you will learn how to implement complex queries, optimize database performance, manage large-scale clusters, and ensure robust failover and backup strategies. What this Book will help me do Understand advanced querying techniques and best practices in data indexing and management. Effectively configure and monitor MongoDB instances for scalability and optimized performance. Master techniques for replication and sharding to support high-availability systems. Deploy MongoDB-based applications seamlessly across on-premise and cloud environments. Learn to integrate MongoDB with modern technologies like big data platforms, containers, and IoT applications. Author(s) Alex Giamas is a seasoned database administrator and developer with significant experience in working with both relational and non-relational databases. Having authored numerous articles and given lectures on MongoDB and other data management technologies, Alex brings practical insights to his writing. He emphasizes real-world applications with examples drawn from his extensive career. Who is it for? This book is designed for developers and database administrators already familiar with MongoDB and basic database concepts, who are looking to enhance their expertise for implementing advanced MongoDB solutions. It is also suitable for professionals aspiring to earn MongoDB certifications and expand their skills to manage large, high-performance database systems efficiently.