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Chapter 4Chapter 4Introduction to Database Development
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Outline Outline
Context for database developmentGoals of database developmentPhases of database developmentCASE tools
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Information SystemInformation System
Student LoanProcessing
System
Loan Applications
Payments Statements
StatusChanges
CashDisbursements
DATABASE
DelinquencyNotices
INPUTS OUTPUTS
PROCESSES
ENVIRONMENTENVIRONMENT
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Traditional Life CycleTraditional Life Cycle
PreliminaryInvestigation
SystemsAnalysis
SystemsDesign
SystemsImplementation
OperationalSystem
Feedback
Feedback
Problem Statement,Feasibility Study
System Requirements
Design Specifications
MaintenanceFeedback
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Development AlternativesDevelopment Alternatives
Difficulties– Operational system is produced late– Rush to begin implementation– Requirements are difficult to capture
Alternative methodologies– Spiral approaches– Rapid application development
Prototypes may reduce risk
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Graphical ModelsGraphical Models
Explicit or implicitData modelProcess modelEnvironment interaction modelEmphasize data model
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Broad Goals of Database Broad Goals of Database DevelopmentDevelopmentDevelop a common vocabularyDefine data meaningEnsure data qualityProvide efficient implementation
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Data Quality MeasuresData Quality Measures
CompletenessLack of ambiguityTimelinessCorrectnessConsistencyReliability
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Database Development PhasesDatabase Development Phases
Conceptual Data Modeling
Logical Database Design
Distributed Database Design
Physical Database Design
ERD
Tables
Distribution Schema
Internal Schema, Populated DB
Data requirements
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Splitting Conceptual DesignSplitting Conceptual Design
View Design
View Integration
Data Requirements
View ERDs
Entity Relationship Diagrams
Conceptual Data Modeling
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Cross Checking RequirementsCross Checking Requirements
DatabaseDevelopment
ERDs, Table Design,...
ApplicationDevelopmentProcess Models,
Interaction Models,Prototypes
SystemRequirements
Data Requirements Application Requirements
OperationalSystem
OperationalDatabase
OperationalApplications
CrossChecking
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Design SkillsDesign Skills
Soft– Qualitative– Degree of subjectivity– People-oriented
Hard– Quantitative– Objective– Intensive data analysis
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Design Skills in PhasesDesign Skills in Phases
Conceptual DataModeling
Logical DatabaseDesign
PhysicalDatabase Design
DistributedDatabase Design
Entity RelationshipDiagrams
Relational DatabaseTables
Distribution Schema
Internal Schema, Populated Database
Data Requirements
Soft
Hard
Design Skills
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Features of CASE ToolsFeatures of CASE Tools
DiagrammingDocumentationAnalysisPrototyping
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Classification of CASE ToolsClassification of CASE Tools
Front-end vs. Back-end– Front-end emphasize data modeling and logical
analysis– Back-end emphasize code generation and physical
designDBMS dependent vs. DBMS independent
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
Commercial CASE ToolsCommercial CASE Tools
PowerDesigner 9Oracle 9i DesignerVisual Studio .Net Enterprise ArchitectERWinER/StudioVisible Analyst
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
ER AssistantER Assistant
CASE tool distributed with the textbookCustomized for this textbook: supports the
ERD notation used in Chapters 5 and 6Drawing toolDiagram checkingEasy to use and powerful tool
McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.
SummarySummary
Background for second part of the course Relationship to information systems
developmentBroad goalsDevelopment phasesCASE tool features
