DBMS年销售15-20亿$US.ppt

Wei Lu 1. Introduction to Database Tianqing Zhang School of Computer (School of Software) SCU 2006 What Is a Database? More than 30 years old An information services industry The most important development in the field of software engineering DBMS年销售15－20亿$US The underlying framework of the information system 信息系统核心 To change the way that many organization operate The Examples of Database Systems 1 Purchases using your credit card 信用卡 A credit card database The checkout assistant A credit card reader Check your credit Add the purchases to database Monthly statements to each cardholder The Examples of Database Systems 2 Booking a flight at the travel agents 航班定座 Flight details database No overbook the same seat on the flight The Examples of Database Systems 3 Using the local library 图书馆 Library database A bar code reader Keep track of books coming in and going out Reserve information Email inform The Examples of Database Systems 4 Taking out insurance 保险 Various insurance organizations database The details of various insurance The best deal The record of taking out insurance The Examples of Database Systems 5 Studying at university Students information database The courses enrolled in The courses grade enrolled in The details of your grant The Examples of Database Systems 6 Using the Internet Many of sites are driven by database applications Online bookstore Traditional File-Based Systems 文件系统 Limitations of the File-Based Approach Separation and isolation of data 数据分离与孤立 2) Duplication of data 数据冗余 3) Program-data dependence 程序依赖于数据 4) Incompatible file formats 文件格式不相容 5) Fixed queries /proliferation of application programs 固定查询/应用程序翻新 Characteristics of the Database Approach 数据库方法 Data: data are raw facts that describe people, objects, and events Database: An integrated collection of related data constitutes a Database(DB). 相关数据 集成 related data, the data represents logically coherent facts about some aspects of the real world that are requir