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

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

© 2002 by Prentice Hall 3 Database System Components

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

© 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

© 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

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

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

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

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

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

© 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

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

© 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

© 2002 by Prentice Hall 15 Defining Tables using Microsoft Access

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

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

© 2002 by Prentice Hall 18 A Browser Data Entry Form

© 2002 by Prentice Hall 19 A Query in Microsoft Access

© 2002 by Prentice Hall 20 A Report in Microsoft Access

© 2002 by Prentice Hall 21 A Menu in Microsoft Access

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

© 2002 by Prentice Hall 23 Top-down Development General requirements to specific requirements A global perspective

© 2002 by Prentice Hall 24 Systems Development Life Cycle Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design

© 2002 by Prentice Hall 25 Systems Development Life Cycle 1.Project Identification/Selection 2.Project Initiation/Planning 3.Analysis 4.Logical Design 5.Physical Design 6.Implementation 7.Maintenance

© 2002 by Prentice Hall Project ID/Selection Enterprise Modeling Analyze current DP Justify need for new DB

© 2002 by Prentice Hall Project Initiation/Planning & Analysis Conceptual Data Modeling ID scope of DB requirements Analyze overall data requirements Develop preliminary data model

© 2002 by Prentice Hall Logical Design Logical Database Design Detail transactions, applications, views etc req’d by DB system ID security, backup, concurrency issues

© 2002 by Prentice Hall Physical Design Physical Database Design Define DB to DBMS Develop DB applications

© 2002 by Prentice Hall Implementation Physical Implementation Install & test DB applications Complete documentation & training

© 2002 by Prentice Hall Maintenance DB Maintenance Ensure DB meeting needs/reqs Performance tuning Backup/Recovery

© 2002 by Prentice Hall 32 Prototype Development Develop portions of the database and submit to users for feedback, refinement, and enhancement

© 2002 by Prentice Hall 33 ID Problem Develop Prototype Implement Prototype Revise Prototype Prototype Development Convert to Production

© 2002 by Prentice Hall 34 Bottom-up Development Specific requirements to general requirements Typically faster and less risky

© 2002 by Prentice Hall 35 Project Management: People Systems analysts Database analysts Users Programmers Database/data administrators Systems programmers, network administrators, testers, technical writers

© 2002 by Prentice Hall 36 Shows time estimates of tasks Project Management: Gantt Chart

© 2002 by Prentice Hall 37 The Data Model A data model defines and graphically depicts the data structure and relationships among the data

© 2002 by Prentice Hall 38 Data Modeling Creation Interviewing users Documenting requirements Building a data model Building a database prototype A process of inference –Working backwards

© 2002 by Prentice Hall 39 Common Data Models Entity-Relationship Model Semantic Object Model

© 2002 by Prentice Hall 40 David M. Kroenke Database Processing Eighth Edition Chapter 2 Introduction to Database Development