说明：  1、项目背景：数据库原理课程设计 2、编写目的：掌握数据库设计原理及相关软件的使用 3、软件定义：学生信息管理系统 4、开发环境：Power builder 9.0
(1, Project Background: Database principles of curriculum design 2, the preparation of Objective: To master the principles of database design and related software 3, software-defined: Student Information Management System 4, the development environment: Power builder 9.0)