Database Systems: Concepts, Design and Applications, 2nd Edition

CHAPTER10

Normalization

10.1 INTRODUCTION

Relational database tables derived from ER models or from some other design method, suffer from serious problems in terms of performance, integrity and maintainability. A large database defined as a single table, results into a large amount of redundant data. Storing of large numbers of values of redundant nature can result in lengthy search operations for just a small number of target rows. It can also result in long and expensive updates. In other words, it becomes generally inefficient, error-prone and difficult in managing this large number of values. Fig. 10.1 illustrates a situation of a large single database of relation STUDENT-INFO (an example from Fig. 9.15 (a) of the previous chapter 9) with ...