ruby-on-rails - ActiveRecord 关联和范围哦，我的

Question

我正在尝试弄清楚如何从多个表中提取数据并理解它。

我有 events、occurrences 和 venues 表。

以下是到目前为止的模型/协会:

模型/事件.rb:

class Event < ActiveRecord::Base
 has_many :occurences, :dependent => :destroy
 belongs_to :price
 belongs_to :venue
 validates_presence_of :venue
end

模型/ field .rb:

class Venue < ActiveRecord::Base
 has_many :events, :dependent => :destroy
end

模型/occurence.rb:

class Occurence < ActiveRecord::Base
 belongs_to  :event
 scope :today, lambda { where("occurence.datetime_start <= ? AND datetime_end >= ?", Time.now.end_of_day, Time.now) }
 scope :this_week, lambda { where("occurence.datetime_start <= ? AND datetime_end <= ?", Time.now.end_of_day, Time.now.at_end_of_week) }
 scope :next_week, lambda { where("occurence.datetime_start > ? AND datetime_end < ?", Time.now.at_end_of_week, Time.now.at_end_of_week + 1.weeks) }
 scope :this_month, lambda { where("occurence.datetime_start <= ? AND datetime_end >= ?", Time.now.end_of_day, Time.now.at_end_of_month) }
 scope :next_month, lambda { where("occurence.datetime_start >= ? AND datetime_end <= ?", Time.now.at_beginning_of_month + 1.months, Time.now.at_end_of_month + 1.months) }
end

我想在 view/events/index.html.erb 中显示的是今天发生的所有事件的表格，我喜欢做类似的事情:

<% @events.today.each do |event|  %>

并显示所有匹配 .today 范围的事件。

我尝试将范围移动到 event 模型，但没有成功。我应该将范围移动到事件模型吗？到目前为止，我的搜索引导我到“Using scope to return results within multiple DateTime ranges in ActiveRecord”和“Multiple scope in rails 3.0 “但我真的无法从中得到任何东西。

谁能指出我正确的方向？我应该在我的事件模型中创建一个新函数吗？

Answer 1

class Event < ActiveRecord::Base
  has_many :occurences, :dependent => :destroy
  belongs_to :price
  belongs_to :venue
  validates_presence_of :venue

  scope :today, lambda {
    joins(:occurences).where("datetime_start <= ? AND datetime_end >= ?", Time.now.end_of_day, Time.now)
  }
end