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Database Design: Course Overview

Database Design: Course Overview. Course Objectives. Learn Basic database concepts and theories. Basic data modeling principles. Practice Database design Database implementation skills Understand How to build database systems. Course Requirements. Grading Homework Assignments (20%)

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Database Design: Course Overview

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  1. Database Design:Course Overview

  2. Course Objectives • Learn • Basic database concepts and theories. • Basic data modeling principles. • Practice • Database design • Database implementation skills • Understand • How to build database systems Database Design

  3. Course Requirements • Grading • Homework Assignments (20%) • Final Project (80%) • Participation (Extra Credit) • Prerequisites • Basic computer skills (e.g., know how to use PC and Web browser) • Technical background is not required. Database Design

  4. Course Policy • Students are expected to be active participant in class discussions, where they will ask questions, provide insights, and explore ideas. • This class advocates an open book policy of allowing students to consult textbooks, Internet resources, and classmates when working on assignments to facilitate learning and promote collaboration. • The Honor Code is in effect.  With the open book policy, it is especially important to clearly indicate in submitted work any materials used from other sources. Full citation information should be given for such sources. Database Design

  5. Course Resources • Homepage • http://kiyang.kmu.ac.kr/gDB/ • Required Readings • Lecture material and online contents • Supplemental Readings • Databases Demystifiedby Andrew Oppel, March 2004, McGraw-Hill • Absolute Beginner's Guide to Databases (1st edition)by John Petersen; 2002, Que • Access 2007: The Missing Manualby Matthew MacDonald; 2006, Pogue Press Database Design

  6. Database Overview

  7. Database Intro • Data vs. Information • Data is a collection of facts. • Information is data processed for knowledge. • Changing data into information • Organize data so that it can be viewed in a useful form. • What form will the derived information take? • How will information be extracted? • What data to collect, how & why? • Requirements • Identify context of data • Organize • Summarize Database Design

  8. Data into Information:Identify Context • Data • Obama, Barack H. 19610804 • Bush, George H W. 19240612 • Bush, George W. 19460706 • Clinton, William J. 19460819 • Carter, James E. 19241001 • Context • Living presidents, United States, 2011/1/1 • Name (last name, first name middle initial), birthdate (YYYYMMDD) • Class Roster, Database System Course, LIS Department, KMU, Spring 2011 • Name (last name, first name middle initial), student ID Database Design

  9. Data into Information:Organize Data • Identify metadata • Course Title: Database System • Course Number: 28149-02 • Credit Hours: 3.0 • Class Time: Tuesday 9 - 10:15 a.m. Thursday 10:30 – 11:45 a.m. • Semester: Spring 2011 • Instructor: Yang, Kiduk • Department Library and Information Science • School Keimyung University • Identify additional data items. • Student Status: Undergraduate Senior • GPA: 3.7 • Major: MIS Database Design

  10. Data into Information:Summarize • Patterns, Trends & Visualization Enrollment Pie Chart Enrollment over Time 15% CS 15% TCOM 45% LIS 10% IST 15% ACCT CS = Computer Science ACCT = Accounting LIS = Library & Information Science TCOM = Telecommunication Database Design

  11. Database Intro • Purpose • Store/retrieve/viewdata efficiently & effectively. • Characteristics • A collection of organized data relatedto a particular subject/purpose • Structured data, security, control • Database management system • data storage, processing, retrieval • User Interface • data entry, search, view/report Database Design

  12. Database: Definitions • Database • is collection of related data and its metadata organized in a structured format • for optimized information management • Database Management System (DBMS) • is a software that enables easy creation, access, and modification of databases • for efficient and effective database management • Database System • is an integrated system of hardware, software, people, procedures, and data • that define and regulate the collection, storage, management, and use of data within a database environment Database Design

  13. Database Management System - manages interaction between end users and database Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

  14. Database System Environment • Hardware • Software - OS - DBMS - Applications • People • Procedures • Data Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

  15. Evolution of Data Models • Timeline 1970s 1980s 1990s 2000+ 1960s File-based Hierarchical Object-oriented Network Relational Web-based Entity-Relationship Database Design

  16. Database: Historical Roots • Manual File System • to keep track of data • used tagged file folders in a filing cabinet • organized according to expected use • e.g. file per customer • easy to create, but hard to • locate data • aggregate/summarize data • Computerized File System • to accommodate the data growth and information need • manual file system structures were duplicated in the computer • Data Processing (DP) specialists wrote customized programs to • write, delete, update data (i.e. management) • extract and present data in various formats (i.e. report) Database Design

  17. File System: Example Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

  18. File System: Weakness • Weakness • “Islands of data” in scattered file systems. • Problems • Duplication • same data may be stored in multiple files • Inconsistency • same data may be stored by different names in different format • Rigidity • requires customized programming to implement any changes • cannot do ad-hoc queries • Implications • Waste of space • Data inaccuracies • High overhead of data manipulation and maintenance Database Design

  19. File System: Problem Case CUSTOMER file AGENT file SALES file AGENT (20 char) A_Name (15 char) A_Name (20 char) Carol J. Smith Carol Johnson Carol T. Johnson - inconsistent field name, field size- inconsistent data values - data duplication Database Design

  20. Database System vs. File System Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

  21. Relational Database • Problems with legacy database systems • Requiredexcessive effort to maintain • Data manipulation (programs) too dependent on physical file structure • Hard to manipulate by end-users • No capacity for ad-hoc query (must rely on DB programmers). • Evolution in Data Organization • E. F. Codd’s Relational Model proposal • Separated the notion of physical representation (machine-view) from logical representation (human-view) • Considered ingenious but computationally impractical in 1970 • Relational Database Model • Dominant database model of today • Eliminated pointers and used tables to represent data • Tables • flexible logical structure for data representation • a series of row/column intersections • related by sharing common entity characteristic(s) Database Design

  22. Relational Database: Example • Provides a logical “human-level” view of the data and associations among groups of data (i.e., tables) Database Design

  23. Entity Relationship Model • PeterChen’s Landmark Paper in 1976 • “The Relationship Model: Toward a Unified View of Data” • Graphical representation of entities and their relationships • Entity Relationship (ER) Model • Based on Entity, Attributes & Relationships • Entity is a thing about which data are to be collected and stored • e.g. EMPLOYEE • Attributes are characteristics of the entity • e.g. SSN, last name, first name • Relationships describe an associations between entities • i.e. 1:M, M:N, 1:1 • Complements the relational data model concepts • Helps to visualize structure and content of data groups • entity is mapped to a relational table • Tool for conceptual data modeling (higher level representation) • Represented in an Entity Relationship Diagram (ERD) • Formalizes a way to describe relationships between groups of data Database Design

  24. E-R Diagram: Chen Model • Entity • represented by a rectangle with its name in capital letters. • Relationships • represented by an active or passive verb inside the diamond that connects the related entities. • Connectivities • i.e., types of relationship • written next to each entity box. Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

  25. E-R Diagram: Crow’s Foot Model • Entity • represented by a rectangle with its name in capital letters. • Relationships • represented by an active or passive verb that connects the related entities. • Connectivities • indicated by symbols next to entities. • 2 vertical lines for 1 • “crow’s foot” for M Database Systems: Design, Implementation, & Management: Rob & Coronel Database Design

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