tailieunhanh - Lecture Database concepts (3rd Edition): Chapter 1 - David M. Kroenke, David J. Auer
Chapter 1 - Getting started. After completing this unit, you should be able to: Identify the purpose and scope of this book, know the potential problems with lists, understand the reasons for using a database, understand how related tables avoid the problems of lists, learn the components of database system, learn the elements of a database, learn the purpose of the database management system (DBMS), understand the functions of a database application. | Getting Started Chapter One DAVID M. KROENKE and DAVID J. AUER DATABASE CONCEPTS, 3rd Edition Chapter Objectives Identify the purpose and scope of this book Know the potential problems with lists Understand the reasons for using a database Understand how related tables avoid the problems of lists Learn the components of database system Learn the elements of a database Learn the purpose of the database management system (DBMS) Understand the functions of a database application 1- Purpose of a Database The purpose of a database is to keep track of things Unlike a list or spreadsheet, a database may store information that is more complicated than a simple list 1- Problems with Lists: Redundancy In a list, each row is intended to stand on its own. As a result, the same information may be entered several times For Example: A list of Projects may include the Project Manager’s Name, ID, and Phone Extension. If a particular person is managing 10 projects, his/her information would have to be entered 10 times 1- Problems with Lists: Multiple Themes In a list, each row may contain information on more than one theme. As a result, needed information may appear in the lists only if information on other themes is also present For Example: A list of Projects may include Project Manager information (Name, ID, and Phone Extension) and Project information (Name, ID, StartDate, Budget) in the same row. 1- List Modification Issues Redundancy and multiple themes create modification problems Deletion problems Update problems Insertion problems 1- List Modification Issues 1- Addressing the Information Complexities Relational databases are designed to address many of the information complexity issues 1- Relational Databases A relational database stores information in tables. Each informational topic is stored in its own table In essence, a relational database will break-up a list into several parts. One part for each theme in the list A Project List would be . | Getting Started Chapter One DAVID M. KROENKE and DAVID J. AUER DATABASE CONCEPTS, 3rd Edition Chapter Objectives Identify the purpose and scope of this book Know the potential problems with lists Understand the reasons for using a database Understand how related tables avoid the problems of lists Learn the components of database system Learn the elements of a database Learn the purpose of the database management system (DBMS) Understand the functions of a database application 1- Purpose of a Database The purpose of a database is to keep track of things Unlike a list or spreadsheet, a database may store information that is more complicated than a simple list 1- Problems with Lists: Redundancy In a list, each row is intended to stand on its own. As a result, the same information may be entered several times For Example: A list of Projects may include the Project Manager’s Name, ID, and Phone Extension. If a particular person is managing 10 projects, his/her information would .
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