English | 2018 | ISBN: 9353161392 | 432 Pages | PDF | 10 MB
This book is tailor made for the course on DatabaseManagement Systems for CSE and IT streams. It provides simple but comprehensiveexplanation of fundamentals of database management systems. It focuses onbuilding database applications by emphasizing on concepts that are thefoundation of database processing
Chapter 1 introduces the subject with a simple example of a cricket database and its features followed by a definition of the term ‘database’. A number of popular websites are listed to illustrate the amount of information that many websites now have and is required to be stored in databases. Chapter 2 discusses the Entity-Relationship model in detail. Representing an Entity-Relationship model by an Entity-Relationship diagram is explained along with generalization, specialization and aggregation concepts. Chapter 3 describes the relational model and its three major components, viz., data structure, data manipulation and data integrity. Mapping of the E-R model to the relational model is explained. This is supported by a brief description of older database models: hierarchical and network models. Chapter 4 elucidates data manipulation in relational model including relational algebra and relational calculus. A number of examples of their use are also presented. Chapter 5 on SQL discusses data retrieval features of SQL using simple examples that involve only one table, followed by examples that involve more than one table using joins and subqueries, as well as built-in functions and GROUPING and HAVING clauses. Use of SQL in enforcing data integrity is also mentioned. Chapter 6 explains theoretical basis of normalization using the concept of functional dependency followed by a study of single-valued normalization and multivalued normalization. The structure of information storage on a magnetic disk is described along with the most commonly used data structures, B-tree and hashing in Chapter 7. In Chapter 8, the concept and properties of a transaction are described along with concepts of a schedule and serializability. Locking and two-phase locking (2PL) are introduced followed by definition of deadlocks, their detection, prevention and resolution.