Software Engineering Professors: staffID, name, sex, age, courseID, department; Courses: courseID, title, hours, classroomID, schedule; Classrooms: classroomID, name, location; File method： Who teaches what (staffID,name,sex,age,department,courseID,title,hours, schedule) Who teaches where (staffID,name,sex,age,department,courseID,location) Who teaches whom (staffID,name,sex,age,department, courseID,studentID,name,sex,age,grade,class,) . 38 Example of DBMS vs. File Method (II) Definition of Database (Application) System（数据库应用系统） A computer system with database technology Components: Computer hardware Database DBMS Application software Users 39 数据库应用程 序 数据库管理系 统（DBMS） 数据库 数据库管理员 （用户） Why Study Database Technology Data are everywhere, databases are everywhere Online stores, real stores Banks, Credit Card Companies Police (Criminal records), Passport Control Airlines and Hotels (reservations) University, etc. $ 40 Summary Database, DBMS, Database application system Data Independency 41