1. © 2002 by Prentice Hall 1 David M. Kroenke Database Processing Eighth Edition Chapter 2 Introduction to Database Development

2. © 2002 by Prentice Hall 2 The Components of the Database System The Database Contents The DBMS The Application Programs The Developers The Users The Database

3. © 2002 by Prentice Hall 3 Database System Components

4. © 2002 by Prentice Hall 4 Database Contents User Data Metadata Indexes Application Metadata

5. © 2002 by Prentice Hall 5 User Data A table of data is called a relation Columns are fields or attributes Rows are entities Relations must be structured properly

6. © 2002 by Prentice Hall 6 Metadata Metadata describes the structure and format of the data and the overall database System tables store metadata –number of tables and table names –number of fields and field names –primary key fields –field names, data types, and length

7. © 2002 by Prentice Hall 7 Indexes Improve performance Improve accessibility (Overhead data)

8. © 2002 by Prentice Hall 8 Application Metadata Stores the structure and format of –forms –reports –queries –other application components

9. © 2002 by Prentice Hall 9 The DBMS Design Tools Subsystem Run-Time Subsystem DBMS Engine

10. © 2002 by Prentice Hall 10 Design Tools Subsystem Tools to design and develop –tables –forms –queries –reports Programming Languages –macros –languages

11. © 2002 by Prentice Hall 11 Run-Time Subsystem Processes database components created by design tools

12. © 2002 by Prentice Hall 12 DBMS Engine Intermediary between the design tools and run-time subsystems and the data Also handles... –transaction management –locking –backup and recovery

13. © 2002 by Prentice Hall 13 Creating the Database Defining the database schema Creating the tables Defining the relationships among the tables

14. © 2002 by Prentice Hall 14 The Database Schema Defines a database’s structure –Tables - subjects within the database –Relationships - one-to-many or 1:N –Domains - set of values a column may have –Business rules - restrictions on data values

15. © 2002 by Prentice Hall 15 Defining Tables using Microsoft Access

16. © 2002 by Prentice Hall 16 Defining Relationships Among the Tables using Microsoft Access

17. © 2002 by Prentice Hall 17 Components of Applications Forms Queries Reports Menus Application Programs

18. © 2002 by Prentice Hall 18 A Browser Data Entry Form

19. © 2002 by Prentice Hall 19 A Query in Microsoft Access

20. © 2002 by Prentice Hall 20 A Report in Microsoft Access

21. © 2002 by Prentice Hall 21 A Menu in Microsoft Access

22. © 2002 by Prentice Hall 22 Database Development Approaches Prototype Top-down development Bottom-up development

23. © 2002 by Prentice Hall 23 Prototype Development Develop portions of the database and submit to users for feedback, refinement, and enhancement

24. © 2002 by Prentice Hall 24 Top-down Development General requirements to specific requirements A global perspective

25. © 2002 by Prentice Hall 25 Bottom-up Development Specific requirements to general requirements Typically faster and less risky

26. © 2002 by Prentice Hall 26 The Data Model A data model defines and graphically depicts the data structure and relationships among the data

27. © 2002 by Prentice Hall 27 Data Modeling Creation Interviewing users Documenting requirements Building a data model Building a database prototype A process of inference –Working backwards

28. © 2002 by Prentice Hall 28 Common Data Models Entity-Relationship Model Semantic Object Model

29. © 2002 by Prentice Hall 29 David M. Kroenke Database Processing Eighth Edition Chapter 2 Introduction to Database Development