THE DATABASE APPROACH - Database Design and Development: An Essential Guide for IT Professionals - page 19

Related data elements. The data elements in a database are not disjointed struc-
tures without any relationships among them. These are related among themselves
and also pertinent to the particular organization.

Information needs. The collection of data elements in a database is there for
a specific purpose. That purpose is to satisfy and meet the information needs of
the organization. In a database for a bank, you will find data elements that are
pertinent to the bank's business. You will find customer's bank balances and ATM
transactions. You will not find data elements relating to a student's major and
examination grades that belong in a database for a university. You will not find a
patient's medical history that really belongs in a database for a medical center.

Shared. All authorized users in an organization can share the information stored
in its database. Integrated information is kept in the database for the purpose of
sharing so that all user groups may collaborate and accomplish the organization's
objectives.

Data-Driven, Not Process-Driven

When an organization adopts a database approach to managing corporate data, the
very method of designing and implementing applications changes. Traditionally,
when you design and implement an application with file-oriented data systems, you
use a process-driven approach. That method changes with database systems. You
shift your design and implementation method to a data-driven approach. Figure
1-6 shows the difference between the two methods.
In both methods, you begin with the definition of requirements. However, there
is an essential difference between the two methods. In the process-driven method,

Process-driven
approach

Data-driven
approach

versus

Requirements
definition

Requirements
definition

Process
Design

Data
Design

Process
Design

Data
Design

Imple-
mentation

Imple-
mentation

Figure 1-6 Data-driven, not process-driven.