Browse Books

Reviewer: Vasant B. Kaujalgi

Modern Information Systems make use of Relational Data Base Systems (RDBMS). Access to the data is possible in a number of ways by the users. SQL (Structuring Query Language) is being developed as a de facto standard for the last two decades. The present standard of SQL-92 is being used for the last decade. Higher-level languages (COBOL, C etc.) make use of embedded SQL instructions for access to such RDBMS. As the popularity of SQL-92 is very high, and as the technology is also advancing, efforts were being made to improve the standards by organizations like ANSI (American National Standards Institute) and ISO (International Organization for Standards). SQL:1999 is the new standard for SQL which is based on the requirements of various users and developers. This standard also keeps pace with the present complexity level of the Information Systems. The present book entitled "SQL:1999 - Understanding Relational Language Components" by Jim Melton and Alan Simon is the appropriate book on the topic of SQL:1999. As the authors state," It is a book for the users who want to understand the full breadth of the SQL:1999 Language". The book starts with Chapter 1, giving overview of RDBM, tables and concept of normalization. The relevance of XML (Extensible Markup Language) to SQL is also described. Chapter 2 describes SQL:1999 with brief descriptions of CLI (Call-Level Interface), PSM (Persistent Stored Modules) and OLB (Object Language Bindings). The core SQL:1999 is also covered here and in one of the Appendices. The following three chapters cover details of SQL:1999 and important differences with SQL-92 concerned with table creation, data manipulation, DDL (Data Description Language), functions and expressions. In Chapter 6, advanced features of SQL:1999 like Case, Cast and Row Value are described. Chapter 7 is concerned with the predicates and specifically the use of SIMILAR. The next chapter lists the enhanced features of JOIN in SQL:1999. SQL query expressions have been enlarged to include WITH, CUBE, ROLLUP, WITH RECURSIVE which are described in Chapter 9. The concept of integrity is important and the role of foreign key is elaborated in Chapter 10. Concept of TRIGGER has been standardized only in SQL:1999 and it is described in detail in Chapter 11. Chapter 12 shows various ways to access the data through real-world applications, particularly, using higher-level languages and module languages. Concept of CURSOR is fundamental in the use of SQL which is described in the next chapter. As different users through different application programs access the relational database at the same time, privileges and security are very important which are emphasized in the next Chapter. The concept and use of ACID property of a transaction processing system is the subject matter of Chapter 15. Original concept of Client/Server Architecture is modified to n-tier architecture and routines can be invocated in different ways which are described in Chapters 16 and 17. Dynamic SQL is the detailed topic of Chapter 18 and CLI (Call-Level Interface) with increased facilities compared to API (Application Program Interface) is covered in detail in Chapter 19. The facility of SQLSTATE is a new feature of SQL:1999 for error management as described in Chapter 20. Concepts of non-English features are covered in Chapter 21 and the differences between base table schema and information schema are described in Chapter 22. SQL will get integrated with XML in the next standard of SQL as predicted in Chapter 23. In Appendix B, the details of a case study about a Music and video Store used in the book, are described. Six Annexes of SQL:1999 are described in Appendix C with core SQL 1999 features and differences with SQL-92. Appendix D has different standards bodies concerned with SQL. A brief history of SQL is in Appendix F. This book is an excellent addition to SQL literature and at a proper time when SQL:1999 is published. It is not a textbook and hence there are no examples and glossary. The value of the book is enhanced because of a case study concerned with a Music and Video Store which is used throughout the book for illustration of SQL:1999 features. Even though important references are includes as footnotes, the readers would have welcomed the references also at the end of the book. The book assumes complete familiarity of SQL-92 by the reader It would have helped if the important differences were marked in the text for those readers who may not know all the features of SQL-92. There is no mention whether the code used in the book is available in electronic form. The index is adequate. The book is strongly recommended for programmes, DB Administrators and Systems Analysts because of excellent presentation by the authors about the topic SQL: 1999 which is very important.