3. • A collection of facts in raw form that
can become information after proper
organization or processing.
• Data is the name given to the basic
facts and entities such as name and
numbers.
• Data can be represented in the form of:
Numbers and Words;
Images, Sounds, Multimedia, etc.
Data
6. File
The collection of related records with fields is called a file. Data in a
database is saved on the computer as a data file and contains data on a
particular topic, e.g., A Student File.
Record
The collection of related fields is called a record. A record is a collection of
organized data of a particular student e.g., Ameen.
Field
A field is a smallest logical unit containing meaningful information in a file
i.e., combination of multiple related characters. A field is part of record that
holds a particular piece of data, e.g., Roll No, Name.
Field, Record and File
7. Field
Record
Here are sample records from a Student data file made up of different
fields:
Sample Fields, Records and File
Roll No Name Class Address
1 Imran 4th Sem Bhera
2 Ameen 4th Sem Chhungan
Table: A Student File
8. Database
A database is an organized, structured collection of
similar information.
A collection of data is referred to as database.
e.g. 1. record of students stored in a student files.
2. information stored over internet.
A database can be stored on paper (manual) or on a
computer (electronic).
A collection of data files integrated and organized into a
single comprehensive file system that is arranged to
minimize duplication of data, and to provide convenient
access to information within that system to satisfy a wide
variety of our needs.
9. • A program that is used for organising data on a computer is
called a database package.
• Data is organised in a database as files, records and fields:
10. To handle large amounts of data
To satisfy multiple users
To make data input faster
To make information retrieval
faster
To provide greater accuracy
To provide good security
Why do we need a database?
We need database:
11. Databases are used by many organisations for various
purposes such as:
Hospitals for preparing patients histories
Govt. Departments for maintaining employees records
Colleges and schools for maintaining students records
Various companies for maintaining import and export
records
A University for maintaining information concerning
students, courses and grades in a university environment
Banks for preparing accounts reports
What is a Database used for?
17. Traditional File Approach
Database File Approach
It was an early attempt to computerize the manual filing system that we
are all familiar with. A file system is a method for storing and organizing
computer files and the data to make it easy to find them. The application
written in C/C++ like programming languages work through this system.
It is the software system that allows the user to define create and maintain
a database and also provides controlled access to the data. DBMS is an
intermediate layer between the programs and data. The following are the
examples of database management system:
• Computerized library system
• Automated Teller Machines (ATM)
• Flight Reservation System
20. • This system stores permanent records in
various files.
• Application programs are required to extract
records from, and add records to the apt files.
• This system coordinates only the physical
access to the data.
• Data is likely to get repeated and cause
redundancy.
• Redundancy can lead to inconsistency of data.
• Multiple user access to the information is
difficult.
• In this system, security of data is low.
• It provides nothing to recover the data.
• Examples are: Programs of C++, COBOL, etc.
D-base management system
• In this system, there exists a collection of
interrelated files.
• There is a set of application program to access
and modify these files.
• This system coordinates both the physical and
logical access to data.
• This system can control the redundancy by
having a centralized database.
• Having no redundancy means no inconsistency.
• Multiple users can update database at the same
time.
• It provides security against unauthorized access.
• It provides backup & recovery for data retrieval.
• Examples are: Programs of Oracle, Sybase, etc.
21. In fo rm a tio n
S y s te m
F ile F ile
In fo rm a tio n
S y s te m
In fo rm a tio n
S y s te m
D a ta b a s e
(c o n s o lid a te d &
in te g ra te d d a ta
fro m file s )
F ile
F ile
In fo rm a tio n
S y s te m
In fo rm a tio n
S y s te m
Traditional File
Processing System
Database
Management System
