Chapter 4 Database Planning, Design and Administration

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Chapter 9 & 10
Database Planning, Design
and Administration
Thomas Connolly, Carolyn Begg, Database System, A
Practical Approach to Design Implementation and
Management, 4th Edition, Addison Wesley
Pg 281~ 341
Learning Outcomes
• Database Application Lifecycle
• DBMS Selection
• Database Administration
Database Application Lifecycles
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Database planning
Systems definition
Requirements collection and analysis
Database design
DBMS selection
Application design
Prototyping
Implementation
Data conversion and loading
Testing
Operational maintenance
Database Planning
• Business goals, plans, and needs
– Mission statements
– Mission objectives
• Current information systems evaluation
– Strengths
– Weaknesses
• IT opportunities for competitive advantages
• Corporate data model
– User needs
– Standards
– Legal requirement
System Definition
• Scope & boundaries
• Applications
Requirement Collection
• Fact-finding techniques
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Interview
Questionnaires
Observation
Documentation
Experience
Requirement Analysis
• Requirements specification technique
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Structured Analysis and Design (SAD)
Data Flow Diagram (DFD)
Hierarchical Input Process Output (HIPO)
Computer-Aided Software Engineering (CASE)
Unified Model Language (UML)
• Approach
– Centralized
– View integration (local data model and global data
model)
– Combination
Database Design
• Approach
– Top-down
– Bottom-up or inside-out
– Mixed
Optimal Logical Data Model
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Structure validity
Simplicity
Expressability
Nonredundancy
Shareability
Extensibility
Integrity
Diagrammatic representation
Phase of Database Design
• Conceptual database design
– Independent of physical consideration
• Logical database design
– Normalization
– Specific data model
• Physical database design
– Relational tables and constraints
– Storage structures and access methods
– Security protection
DBMS Selection
• Steps
– Define terms of reference of study
– Shortlist two or three products
– Evaluate products (feature, comment, rating weight, and score)
• Selection Criteria
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Data definition
Physical definition
Accessibility
Transaction handing
Utilities
Development
Other features
Application Design
• Considerations
– Data
– Transaction type (retrieval, update, or mixture)
• User interface (forms & reports)
– Logical
– Simple
– Error handling
– Help
– Meaningful
– Consistency
– Status
Prototyping
• Type
– Requirement prototyping
– Evolutionary ptototyping
• Pros
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Define user’s requirements
Quick
Feasibility test
Low cost and risk, new technology
• Cons
– Costs
Implementation
• Data definition language (DDL)
• Data manipulation language (DML) or
embedded DML
• Security control
Data Conversion and Loading
• Actual data conversion
• Bridge
Testing
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Learnability
Performance
Robustness (tolerant of user error)
Recoverability
Adapatability
CASE Tools
• Computer-Aided Software Engineering (CASE)
• Types
– Upper-Case: planning to design
– Lower-Case: implementing, test, performance
– Integrated-Case
• Benefits:
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Productivity (effectiveness and efficiency)
Standard
Integration (repository)
Support structured methods
Consistency
Automation
Data Administration Role
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Planning
Developing and maintaining standard
Developing policy & procedure
Design conceptual and logical database
Database Administration Role
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Physical database design
Security & integrity control
Performance monitoring
Tuning database
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