PostgreSQL is the world's most advanced open-source relational database. For developers and administrators who need their systems to stay fast, correct, and dependable, it provides a stable foundation for everything from a single application to a high-availability cluster. This book is a practical guide to PostgreSQL. It covers architecture fundamentals, database design, transaction management, indexing, advanced SQL, query performance, views, stored procedures and functions, authentication and security, backup and recovery, high availability, and extensions. It also covers monitoring, logging, diagnostics, migration, and vector search, so you can take a working database through to production. Each chapter includes runnable SQL examples you can reuse in your own projects, with an emphasis on clean, correct code and modern PostgreSQL practice.