1. The Database Environment
IST - 331
Instructor: Victor Matos

2. Definitions
Data: Meaningful facts, text, graphics, images, sound, video segments.
Database: An organized collection of logically related data.
Information: Data processed to be useful in decision making.
Metadata: Data that describes data.

3. Figure 1-1a Data in Context

4. Figure 1-1b Summarized data

5. Disadvantages of File Processing Systems
Data Dependence
Data Redundancy (Duplication of data)
Limited Data Sharing
Lengthy Development Times
Excessive Program Maintenance

6. Figure 1-2 Three file processing systems at Pine Valley Furniture

7. Advantages of the Database Approach
Minimal Data Redundancy/Improved Consistency
Data Integration
Multiple Relationships

8. Database Management System
A DBMS is a data storage and retrieval system which permits data to be stored non-redundantly while making it appear to the user as if the data is well-integrated.

9. Advantages of the Database Approach
Data Independence/Reduced Maintenance
Improved Data Sharing
Increased Application Development Productivity
Enforcement of Standards
Improved Data Quality (Constraints)
Better Data Accessibility/ Responsiveness
Security, Backup/Recovery, Concurrency

10. Costs and Risks of the Database Approach
New, Specialized Personnel
Installation Management Cost and Complexity
Conversion Costs
Need for Explicit Backup and Recovery
Organizational Conflict

11. Figure 1-3 Segment from enterprise data model

12. Figure 1-4a Order and Order_Line tables

13. Figure 1-4b Product and Customer tables

14. Figure 1-5 Client/server system for Pine Valley Furniture Company

15. Figure 1-6 Customer invoice (Pine Valley Furniture Company)

16. The Range of Database Applications
Personal Database
Workgroup Database
Department Database
Enterprise Database

17. Figure 1-7 Typical data from a personal computer database

18. Figure 1-8 Workgroup database with local area network

19. Figure 1-9 An example of departmental database (Personnel Department)

20. Figure 1-10 An enterprise data warehouse

21. Components of the Database Environment
CASE Tools
Repository
Database Management System (DBMS)
Database
Application Programs
User Interface
Data Administrators
System Developers
End Users

22. Figure 1-11 Components of the database environment

23. Evolution of Database Systems
Hierarchical and Network (Legacy)
Relational
Object-oriented
Object-relational

24. Figure 1-12 Evolution of database technologies