第一个模块是用户模块。管理员,学生,讲师或嘉宾是从系统中受益的用户,他们参与此模块。管理员将为每个用户分配角色作为学生或讲师。每个角色都有不同的权限,即讲师可以上传作业和课程资料,创建在线测验和单个上传文件。用户拥有诸如用户ID,注册日期,最新登录日期,登录帐户,密码,名字,姓氏以及其他所需详细信息等信息。只要说学生证和讲师ID不能成为主键。因此,当分配ID和我的测验ID是主键时,我想如何声明分配或测验ID在功能上依赖于讲师?基于我的函数依赖关系,我不太确定我如何将它们与函数依赖关系联系起来?编写功能依赖关系
Entity: User
User(user ID, student ID, lecturer ID, guest ID, course ID, assignment ID, quiz ID, file upload, date of registration, date of latest logon, login account, password, first name, last name, e-mail, birthdate)
Functional dependency
user ID -> {student ID, lecturer ID, guest ID, date of registration, date of latest logon, login account, password, first name, last name, e-mail, birthdate}
lecturer ID -> {course ID, assignment ID, quiz ID, file upload}
Full dependency
user ID, lecturer ID -> {student ID, guest ID, course ID, assignment ID, quiz ID, file upload, date of registration, date of latest logon, login account, password, first name, last name, e-mail, birthdate}
我编辑了我的答案,我只是想问我在任何意义上我是否正确?谢谢.. – Synetrix 2014-11-06 14:31:39