Page 99 - DCAP516_COMPUTER_SECURITY

Unit 8: Introduction to Databases

immediate processing or interactive processing include air traffic and banking. In air Notes
traffic, as the flying speed increases control decisions have to be taken more quickly.
Therefore, interactive processing is the only suitable system for air traffic control. In
banking, where a customer is at the counter and the time to update his bank account will
naturally take more time if done manually, a computer can give full updated details of the
customer’s account within seconds processing. For this, a customer is given the needed
information mostly by interactive way.

Task

1. Differentiate between batch processing and Online processing.
2. Give two examples of following:
(i) batch processing

(ii) Online processing
8.6 Data Representation

We know that data is usually a combination of numbers, characters and special characters. This
data has to be worked upon by the computer as well as it has to be ported from place to place, i.e.
data has to flow from place to place within the computer hardware. As the computer is an
electronic device and it works with electronic pulses, this data or information should be in a
form that is machine readable and understandable. For this reason, data has to be represented in
the form of electronic pulses.

The data has to be converted into electronic pulses and each pulse should be identified with a
code. For these reasons, the data is converted into numeric format first, by using worldwide
standard called ASCII i.e. American Standard Code for Information Interchange, where each and
every character, special character and keystrokes have numerical equivalent. Thus using this
equivalent, the data can be interchanged into numeric format. For the numeric conversion, we
use number systems; each number system has a radix or base, which indicates the number of
digits in that number system. In any number system, there is an ordered set of symbols known
as digit with rules defined for performing arithmetic operations like addition, multiplication,
etc.
8.7 Introduction to Database

A database can be defined in various ways; for example, a database is a collection of structured
data. The structure of the data is independent of any particular application. A database is a file of
data structured in such a way that it may serve a number of applications without its structure
being dictated by any one of those applications, the concept queuing that programs are written
round the database rather than files being structured to meet the needs of a particular program.
The centre of any information system is its database, which is a collection of the data resources
of an organization designed to meet the requirements of the company for processing and
retrieving information by decision-makers. One important use of database is to target more
precise marketing efforts. In developed countries, the latest trend in management information
systems is the executive information system which is used by senior managers.
A database can be termed as a repository of data. A collection of actual data which constitutes the
information regarding an organisation is stored in a database. For example, there are 1,000

LOVELY PROFESSIONAL UNIVERSITY 93