Hash tables, when implemented and used appropriately, are exceptionally efficient data structures for representing sets and lookup tables, providing low overhead, constant time, insertion, deletion, and lookup operations. This book walks you through the implementation of efficient hash tables and the pros and cons of different design choices when building tables.
Before you buy this book, be aware that it is a work in progress! I am updating it one chapter at a time. If you buy this version, though, you also get all the updates coming later.
If you buy the book and want to be informed about updates when I add new chapters or modify the existing material, you can sign up to this mailing list: https://mailchi.mp/cd8de11c9540/updates-to-the-joys-of-hashing