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ruby-on-rails - Rails 协会 : Teacher Student Classes

转载 作者:行者123 更新时间:2023-12-05 07:57:31 25 4
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我仍在学习如何使用 Rails 发挥创意,并且可以使用以下 Rails 协会的最佳实践指南:

我有三个模型,教师、学生和类(class)。教师可以教授任意数量的类(class),学生可以加入任意数量的类(class),一个类(class)只能由一名教师教授,但可以有 1-5 名学生。

我的第一个假设是使用以下内容:

类:属于老师有_很多学生

教师:has_many:学生通过 => 类(class)

学生们:has_many: 教师通过 => classes

我不知道这是否合适,我已经看到了加入表的建议。任何指导将不胜感激 !

更新:鉴于以下有用用户的反馈,我建议采用以下解决方案。有人可以验证这一点吗?因为一个学生可以有多个类(class),属于一个类(class),反之亦然,所以我需要两个连接表

class ClassRoomEnrollment < ActiveRecord::Base
belongs_to :students
belongs_to :classrooms
end

class ClassRoom < ActiveRecord::Base
belongs_to :teacher
has_many :students through: classroomenrollment

end

class Teacher < ActiveRecord::Base
has_many :students :through => :classrooms
end

class Student < ActiveRecord::Base
has_many :teachers :through => :classrooms
has_many :classrooms through: classroomenrollment
end

最佳答案

Class 不是一个好名字,ClassRoom 更好

class ClassRoom < ActiveRecord::Base
belongs_to :teacher
belongs_to :student # if I have well understand, this is the right association

#some validations rules
validates :<fieldname>, :<rule> => <value>, ...

#callback like :before_save or :after_save, ....
end

class Teacher < ActiveRecord::Base
has_many :students :through => :classrooms, :depend => :destroy

#some validations rules
validates :<fieldname>, :<rule> => <value>, ...

#callback like :before_save or :after_save, ....
end

class Student < ActiveRecord::Base
has_many :teachers :through => :classrooms, :depend => :destroy

#some validations rules
validates :<fieldname>, :<rule> => <value>, ...

#callback like :before_save or :after_save, ....
end

通过关联(has_many、has_one、belongs_to)自动创建通过表的连接。你可以访问一个老师的所有学生,比如

teacher.classrooms.first.students e.g.

希望对你有帮助

关于ruby-on-rails - Rails 协会 : Teacher Student Classes,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27077040/

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