Fundamentals of
Database
Arif Ali Bhatti
Assistant Professor
Dept. of Lib and Inf Sc & Archive Studies
University of Sindh, Jamshoro
What is a database
A database is any organized collection of data. Some
examples of databases you may encounter in your
daily life are:
 a telephone book
 T.V. Guide
 airline reservation system
 motor vehicle registration records
 papers in your filing cabinet
 files on your computer hard drive.
General:
• A database is any collection of related data.
Restrictive:
• A database is a persistent, logically coherent collection
of inherently meaningful data, relevant to some aspects
of the real world.
Data vs. information:
What is the difference?
What is data?

Data can be defined in
many ways.
Information science
defines data as
unprocessed
information.
What is information?



Information is data that
have been organized and
communicated in a
coherent and meaningful
manner.
Data is converted into
information, and
information is converted
into knowledge.
Knowledge; information
evaluated and organized
so that it can be used
purposefully.
Why do we need a database?
Keep records of our:
 Clients
 Staff
 Volunteers
To keep a record of
activities and
interventions;
Keep sales records;
Develop reports;
Perform research
Longitudinal tracking
What is the ultimate purpose of
a database management
system?
Is to transform
Data
Information
Knowledge
Action
More about database definition
What is a database?
Quite simply, it’s an organized collection of data.
A database management system (DBMS) such
as Access, FileMaker, Lotus Notes, Oracle or
SQL Server which provides you with the
software tools you need to organize that data in
a flexible manner. It includes tools to add,
modify or delete data from the database, ask
questions (or queries) about the data stored in
the database and produce reports summarizing
selected contents.
Database: A Formal Definition
A database is an ordered collection of related data
elements intended to meet the information needs of an
organization and designed to be shared by multiple users.
Key terms in the definition:
Ordered collection. A database is a collection of data
elements. Not just a random assembly of data structures,
but a collection of data elements put together deliberately
with proper order. The various data elements are linked
together in the most logical manner.
Related data elements. The data elements in a database
are not disjointed structures 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.
TYPES OF DATABASES
Organizations primarily adopt one of two approaches. If the
entire database is
kept in one centralized location, this type of database is a
centralized database. On the other hand, if fragments of the
database are physically placed at various locations, this type
of database is a distributed database.
Each type has its own benefits and shortcomings. Again,
whether an enterprise adopts a centralized or a distributed
approach depends on the organizational setup and the
information requirements.
Let us review the two types.
Distributed
Database Management System
What does “managing
information” mean?
Making information work for us
Making information useful
Avoiding "accidental disorganisation”
Making information easily accessible and
integrated with the rest of our work
Managing as re-organising
We often need to access and re-sort data for
various uses. These may include:




Creating mailing lists
Writing management reports
Generating lists of selected news stories
Identifying various client needs
Can you add to the list?
Managing as re-processing
The processing power of a database allows it to:

Sort

Match

Link

Aggregate

Skip fields

Calculate

Arrange
DBMS Functions
Performs functions that guarantee
integrity and consistency of data

Data dictionary management
defines data elements and their relationships

Data storage management
stores data and related data entry forms, report
definitions, etc.

Data transformation and presentation
translates logical requests into commands to
physically locate and retrieve the requested data
DBMS Functions (continued)

Security management
enforces user security and data privacy within
database

Multi-user access control
creates structures that allow multiple users to
access the data

Backup and recovery management
provides backup and data recovery procedures
DBMS Functions (continued)

Data integrity management
promotes and enforces integrity rules to
eliminate data integrity problems

Database access languages and
application programming interfaces
provides data access through a query language

Database communication interfaces
allows database to accept end-user requests
within a computer network environment
The Database System
Environment
Database system is composed of 5
main parts:
1.
2.
Hardware
Software
Operating system software
DBMS software
Application programs and utility software
3.
4.
5.
People
Procedures
Data
Basic File Terminology
Table
A Database with Multiple Tables
[1]
Publishers
Books
Customers
Authors
Inventory
Orders
Field (Column)
Customers
a field
Record (Row)
Customers
a record