Title: Database Management Systems Author: Alexes Leon, Mathews Leon Publisher: Leon Press, Chennai & Vikas Publishing House, New Delhi. Pages: 988 / Price: Rs 350/-

While solving a crossword it is interesting to note the way our mind works. To find the answer to a cryptic clue like, ‘name of a holy river,’ we not only have to think of all the rivers but also match the number of words in the name to the number of boxes, which in turn has to complete the word in the intersecting column as well.

In this case we understand how our mind analyses its knowledge base (database) to arrive at the appropriate answer. The information age has made it imperative to understand the working of databases in order to optimise their use. Therefore, understanding a database system as well as the procedure of its management is a must for the IT professional as well as for a layman interested in unravelling the mystery of databases.

‘Database Management Systems’ by Alexes Leon and Mathews Leon is a good attempt in this direction. Though it has been written as a text for undergraduate and post-graduate students of computer science and a reference for professionals, the simple and logical style of writing makes interesting reading and is easy to understand, even for those without any previous knowledge of databases.

This book is divided into several parts and covers all the aspects of a database. It starts from basics and progresses to advanced topics in a step-by-step manner.

The introduction has an interesting tidbit on the historical use of databases since the time of the Egyptians and the Incas of South America. After introducing the basics of database management systems and relational database systems, the next part discusses the design architecture and relationship of various entities.

Throughout its lifecycle, information is retrieved from and updated to databases. Therefore, a major part of book is devoted towards this and Structured Query Language (SQL); Query By Example (QBE), Triggers etc, are covered extensively in ‘Query Languages.’

Once a database system is in place it has to be saved from external threats like hacking and viruses, and its integrity maintained through ‘transaction management’ and ‘concurrency control.’ To safeguard against unexpected data loss, various techniques used in ‘backup’ and ‘recovery’ are explained.

The manner in which databases affect our lives becomes apparent when one reads ‘Database applications.’ It deals with interesting topics like customer relationship management (CRM), supply chain management (SCM), and geographic information systems (GIS).

In the last part of the book a few useful appendices are given, like the one on ‘Glossary of Database Items.’ This is a 988-page book and would have been more handy if a CD-ROM had accompanied it. However, the book does fulfil the objectives for which it was created and is a fitting display of the authors’ experience in technology and language.