This comprehensive guide delves into key PostgreSQL topics that are essential for acing technical interviews, emphasizing the transactional aspects of the database system. It highlights the importance of understanding data modeling, including different relationship types and the use of foreign keys, as well as the utilization of PostgreSQL's rich type system like arrays and JSONB. The guide also covers the significance of indexing for optimizing query performance and the use of EXPLAIN ANALYZE for query analysis. It discusses the creation and management of views for data representation, including the concept of autoupdatable views and their limitations. Security aspects such as roles, permissions, and row-level security (RLS) are also explored, along with the use of functions and PL/pgSQL for implementing business logic. Additionally, the guide emphasizes thinking in sets and the benefits of using common table expressions (CTEs) for more readable queries. It encourages practical application of these concepts to truly master PostgreSQL, with a nod to Supabase as a platform for quickly setting up and experimenting with PostgreSQL databases.