Sams Teach Yourself SQL in 24 Hours (5th Edition)

This is the Chinese translation of the fifth edition of Sams Teach Yourself SQL in 24 Hours, co-authored by three authors with long experience in database teaching and consulting, and written for readers with no prior background in SQL. The book is divided into nine parts and 24 chapters. It begins with the definition, history, and command categories of SQL to establish a conceptual framework, then moves into database creation, covering data types, tables and database objects, integrity constraints, normalization and denormalization, as well as data operations such as INSERT, UPDATE, and DELETE and transaction control (COMMIT, ROLLBACK, SAVEPOINT). Parts III and IV focus on query skills: the basic structure of the SELECT statement, comparison and logical operators, summary functions, sorting and grouping, data formatting, date and time handling, and then multi-table joins, subqueries, and combining multiple queries. Parts V through VII discuss indexes and performance tuning, user and privilege management, views, and the system catalog. The final part extends to advanced SQL topics, SQL's expansion into enterprise and Internet environments, and the dialect differences among database products relative to standard SQL. The appendices provide a quick reference to common SQL commands, MySQL installation and setup of a practice environment, answers to the quizzes and exercises in each chapter, and the CREATE TABLE and INSERT statements for the sample tables, so readers can practice as they read. Throughout, the book emphasizes the gap between the standard and its implementations; examples cover major platforms such as Oracle and MySQL, and each chapter includes a summary, Q&A, and practice problems.