Database System Concepts, Avi Silberschatz, Henry F. Korth, S. Sudarshan, 2019 (McGraw-Hill Education) - A comprehensive academic textbook offering a solid foundation in database systems, with thorough coverage of SQL principles and applications.
Learning SQL: Master SQL Fundamentals, Alan Beaulieu, 2020 (O'Reilly Media) - A highly practical book focused on SQL fundamentals, appropriate for beginners to intermediate users working with various relational database systems.
PostgreSQL Documentation, The PostgreSQL Global Development Group, 2025 (The PostgreSQL Global Development Group) - The official documentation for a leading open-source relational database, providing detailed information on SQL commands and their specific implementation within PostgreSQL.