1. Introduction to Databases
Chapter 1
Introduction to Databases
Thomas Connolly, Carolyn Begg, Database System, A Practical Approach to Design Implementation and Management, 4th Edition, Addison Wesley
Pg 3 ~ 26

2. Learning Outcomes Introduction Traditional File-based Systems
Database Approach
Roles in the Database Environment
Advantages & Disadvantages of DBMS

3. Examples of Database Application
Purchases from the supermarket
Purchases using credit card
Booking a holiday at the travel
Using the local library
Taking out insurance
Using the Internet
Studying at university

4. File-based Definition
Collection of application program that perform services for the end users (e.g reports)
Program defines and manages it’s own data

5. File-based Processing

6. Limitations of File-based
Separation and isolation
Duplication
Program & data dependence
Fixed queries
Proliferation of application programs

7. Database Definition System catalog Data abstraction
A collection of self-describing and integrated data files
System catalog
Meta data
Data dictionary
Overhead data
Data abstraction

8. Database Approach Data definition language (DDL)
Data manipulation language (DML)
Structured query language (SQL)
Security system
Integrity system
Concurrency control system
Backup & recovery system
View mechanism

9. Database Management System (DBMS)

10. DBMS Environment Hardware Software Data People Procedure
Client-server architecture
Software
dbms, os, network, application
Data
Schema, subschema, table, attribute
People
Data administrator & database administrator
Database designer: logical & physical
Application programmer
End-user: naive & sophisticated
Procedure
Start, stop, log on, log off, back up, recovery

11. Roles in the Database Environment
Data Administrator (DA)
Management of data resources
Ensure database development support corporate objectives
Database Administrator (DBA)
Physical realization of database
More technically oriented
Database Designers
Logical
Identifying data
Physical
Realization of logical database
Application Programmers
Implement application program for user
End Users (Naïve and Sophisticated)

12. Advantages of DBMS Control redundancy Consistency Integrity Security
Concurrency control
Backup & recovery
Data standard
More information
Data sharing & conflict control
Productivity & accessibility
Economy of scale
Maintenance

13. Limitations of DBMS Complexity Size Cost Software Hardware Conversion
Performance
Vulnerability