databases ? 2015, fall pusan national university ki-joune li
TRANSCRIPT
Databases ?2015, Fall
Pusan National UniversityKi-Joune Li
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Questions
• Q1 – Describe actual political situation in Korea.• Q2 – Make it machine-understandable.
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Overview on Databases
Computer World
Real World
phase 1 phase 2
understanding modeling
implementation design and coding
Application Management
phase 3
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Comparison with Software Lifecycle
Requirement Analysis
Functional Specification
Design
Development Environments
Coding
Test
Maintenance
Software Life Cycle – Waterfall Model
Requirement Analysis
Modeling
Schema Design
DB Environments
Data Collection and Input
Quality Control
Management and Retrieval
DB Life Cycle
part I
part II
part III
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Plan
• Part I – Data Modelingo Understanding it in formal wayso Object-Oriented Data Model (UML Class Diagram)o Relational Data Model (E-R Model)
• Part II – Database Designo Relational Database Schema Design
• Part III – Query Languageo SQL
• Part IV – Semi-Structured Data Modelo XML
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Two different aspects of DB
Logical (or Conceptual) Representation
Physical RepresentationHow to physically organize
data in file systems DBMS Issue
How to conceptually understand and describe
information Database IssueIndependence
Applications are developedon the conceptual understanding
of real worldApplications
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Three Level Schema of Databases
Logical (or Conceptual) Representation
Physical Representation
Independence
Applications
Physical level (schema)
Conceptual level (schema)
External level (schema)
File Processing in Spring Semester