Databases ? 2014, Fall Pusan National University Ki-Joune Li

Questions Q1 – Describe actual political situation in Korea. Q2 – Make it machine-understandable. 2

Overview on Databases Computer World Real World phase 1 phase 2 understanding  modeling implementation  design and coding Application  Management phase 3 3

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 4

Plan Part I – Data Modeling o Understanding it in formal ways o Object-Oriented Data Model (UML Class Diagram) o Relational Data Model (E-R Model) Part II – Database Design o Relational Database Schema Design Part III – Query Language o SQL Part IV – Semi-Structured Data Model o XML 5

Two different aspects of DB Logical (or Conceptual) Representation Physical Representation How to physically organize data in file systems  DBMS Issue How to conceptually understand and describe information  Database Issue Independence Applications are developed on the conceptual understanding of real world Applications 6

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 7