FILE PROCESSING SYSTEM

FILE PROCESSING SYSTEM

1. In a file processing system, data is kept in a computer file placed in a folder or a drive. The operating system provides the file processing system that allows a file to be opened, edited, saved, copied or deleted.

2. A file is a modern equivalent to paper document.

a) The basic unit of data are characters - alphabets, numbers and symbols.

b) Data is organized into a matrix for easier processing by the computer. Each piece of data belongs to a horizontal line and a vertical column.

c) All data under the same column belongs to the same field. Each field has a label and pre-defined format.

d) Each horizontal line is called a record which contains a set of related data that represent an object in the real world. A file is a collection of similar records. The number of records could be from a dozen to a few hundred.

3. Example applications of files are:

a) Log files are generated by a computer system for event reporting.

Example:

Windows system generates files recording error and accompanying details every time the operating system encounters an error. The log is used by technicians or owners for troubleshooting.

b) MS Excel spreadsheet is used to record data for statiscal analysis and report generation.

Example:

Monthly sales of a supermarket product in a few of the company’s branches are recorded in a spreadsheet for statistical analysis and chart generation.

c) Scientific instruments and machines often capture data from sensors and record the result in text files.

Example 1:

A computerized car diagnostic system reads log files generated by the onboard chip in the car for error diagnosis.

Example 2:

An electrocardiogram (ECG) records a patient’s heart condition in files for reference.

Example 3:

Server settings are stored in files to provide configuration inputs to the system.

4. Major disadvantages of a file processing system are:

a) Redundancy

Similar data may have to be kept in more than one place, causing unnecessary duplicates.

b) Data Inconsistency

Data inconsistency is error caused by failure to update all occurrences of the same data located in multiple locations.

c) Data Integrity Problem

It is difficult to ensure that a new input value is accurate and satisfies some rules. A file processing system does not automatically check the inputs.

Example:

Entered value must be positive integers only.

d) Program-Data Dependence

The file system is one part of the access program¹ subsystem. Any change in data may require the program to be rewritten.

e) Data Isolation

Data may be stored in various formats. Sharing, tracking, and access of data related to a task is difficult.

f) Security

It is difficult to share data and yet prevent unauthorized access.

5. Due to the inherent disadvantages of files, data retrieval and updates are difficult and prone to error.

a) Today’s business environment generates huge amounts of data and traffic.

b) Sectors such as banking, airlines, insurance, retailing and digital communication are huge and operate with many branches. Data collected from different branches need to be integrated and managed. This involves a huge amount of effort.

^1. Access program refers to any application program for retrieving data from a repository.