The Importance and use of data dictionaries

Introduction

A data dictionary is a collection of descriptions of the data objects or items in a database for the benefit of programmers and others who need to refer to them. This includes the names of all tables, the table schemas, location of tables, view definitions, details about indexes, access rights etc. Data dictionaries do not contain any actual data from the database, only bookkeeping information for managing it. Without a data dictionary, however, a database management system cannot access data from the database.


Types of Data Dictionaries
Data dictionaries are either passive or active. An active system is always consistent with the database structure, because it is maintained automatically by the system. Programs include an automated data dictionary as part of the program. In this way, all the information about a database is captured into a document as the database is created. Therefore, the database design (showing all...