失物招领系统数据库设计 1 目录 失物招领系统数据库设计 ········································································· 2 一、系统需求分析 ·················································································· 2 （一）问题背景 ·························································································· 2 （二）系统总体目标 ···················································································· 2 （三）系统主要功能 ···················································································· 2 二、概念结构设计 ·················································································· 5 （一）标示实体集 ······················································································· 5 （二）标示联系集： ···················································································· 5 （三）标示属性集 ······················································································· 5 三、逻辑结构设计 ·················································································· 8 （一）初始关系模式 ·················...
