查询通过导轨的has_many [英] Query for has_many through rails

问题描述

协会

 类活动
  的has_many：views_logs
  的has_many：用户，通过：views_logs
结束
 

我想获得的所有用户在广告系列的具体日期等内
意思，我想要做的事，如：
  Campaign.first.users.where（？）

现在，当我查询：

  Campaign.first.users.all
 

我得到所有用户的列表中的某个广告系列中，但我如何才能得到只有那些拥有这些用户的具体日期间仅运动范围。

解决方案

  

我想获得广告活动中所有用户的任何特定日期内

的ActiveRecord协会扩展 ：

 ＃应用程序/模型/ campaign.rb
一流的运动＆LT; ActiveRecord的::基地
   的has_many：用户，通过：view_logs做
      之间的日期，结束日期DEF
         其中（created_at：start_date..end_date）
      结束
   结束
结束@campaign = Campaign.find点¯x
@users = @ campaign.users.between（Date.today  -  2，Date.today.day）
 

-

更新 - 这似乎PGSQL需要时间戳评估日期：

  @users = @ campaign.users.between（Time.now.midnight  -  2.days，Time.now.midnight）
 

区别在于之间 日期 ＆安培; 时间 对象

Association is

class Campaign
  has_many :views_logs
  has_many :users, through: :views_logs
end

I want to get all users in a Campaign within any specific dates etc meaning, I want to do something like: Campaign.first.users.where(?)

Now, when I query:

Campaign.first.users.all

I get list of all users within a certain campaign, but how I can I get only those users which have Campaign between specific date ranges only.

解决方案

I want to get all users in a Campaign within any specific dates

ActiveRecord Association Extension:

#app/models/campaign.rb
class Campaign < ActiveRecord::Base
   has_many :users, through: :view_logs do
      def between start_date, end_date
         where(created_at: start_date..end_date)
      end
   end
end

@campaign = Campaign.find x
@users    = @campaign.users.between(Date.today - 2, Date.today.day)

--

Update - it seems PGSQL requires a timestamp to evaluate dates:

@users = @campaign.users.between(Time.now.midnight - 2.days, Time.now.midnight)

The difference being that between Date & Time objects.

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