1. Introduction & History of Database Systems
Unit # 1
Introduction & History of Database Systems

2. Introduction
Introduction
Course Outline
Project
Labs
Grading

3. Queries
What is Data?
What is Database?
What is DBMS?

4. Basics Data Raw facts/details of a subject or universe of discourse.
Database
A shared collection of logically related data, designed to meet the information needs of an organization.
Database Management System (DBMS)
Software that enables users to define, create and maintain the database and provides controlled access to the database

5. What is the importance of data?
Paradigm shift: Data driven business environment
Knowledge and innovation (e.g., knowledge management, business intelligence)
Current Status to identify
replenishment needs
(e.g. Stock in hand)
Performance of vendors
(e.g., supply chain management
Competitor and marketplace information
Customer information (e.g., database marketing, CRM)

6. History of Database Systems
First generation
File based systems
Second generation
Relational databases
Third generation
Object relational databases
Object Oriented databases
……….and others

7. Traditional File-Based System
“A collection of application programs that perform services for the end users such as the production of reports. Each program defines and manages its own data.”

8. Traditional File-Based System
Invoices
Customer
Orders
Invoice Program
Customer Account
Customer Accounts File
Account Report
Program
Customer
Mailing List
Customer Mailings
Mailing List
Program

9. Data Redundancy Customer Order File Customer Account File
Invoice number
Customer account number
Customer name, address, city, state, zip code
Order date
Product code, product description, price, unit
Customer Account File
Account Number
Customer name, mailing address, city, state, zip code
Customer Mailing List File

10. File-Based Systems - Limitations
Separation and isolation of data (one file, one program)
Duplication of data
Loss of data integrity - uncertainty of the correct version of data and no consistency
Data dependence - application program defines the data
Incompatibility of file formats
Fixed queries/proliferation of application programs. Little flexibility in meeting changing information needs

11. Database Database can more technically be defined as:
‘Shared collection of logically related data, and a
description of that data, designed to meet
information needs of an organization.’ OR
‘Self-describing collection of integrated record.’

12. Database Management System (DBMS)
DBMS can be defined as:
“ Software system that enables users to define, create and maintain the database and provides controlled access to the database.”
Database Management System (DBMS) contains not only the data but meta data as well i.e. data about the data

13. Illustrating Metadata