Question

我是一个菜鸟，所以我提前为这个问题缺乏清晰度和/或简单性而道歉。

我正尝试以4种方式对产品index.html.erb中的产品进行排序。其中三个正在运作，但“趋势”功能却没有。我无法通过clock.size订购（这可能与表或时钟和产品之间的关联有关 - 我显然不确定）

任何帮助都会很棒！感谢。

的routes.rb

Kijovo::Application.routes.draw do

root "welcome#index"

get "products/filter/:scope" => "products#index", as: :filtered_products

resources :products do
resources :clocks
end
end

products_controller.rb

class ProductsController < ApplicationController
 before_action :require_signin
 before_action :require_admin, except: [:index, :show]
 before_action :set_product, only: [:show, :edit, :update, :destroy]

def index

@product = Product.find_by(params[:id])

case params[:scope] 
  when 'past'
    @products = Product.past
  when 'upcoming'
    @products = Product.upcoming
  when 'tba'
    @products = Product.tba
  else
    @products = Product.trending
  end

end

product.rb（产品型号）

 class Product < ActiveRecord::Base
  has_many :clocks, dependent: :destroy
  has_many :clockers, through: :clocks, source: :user

 before_validation :generate_slug

 validates :slug, uniqueness: true


  # scope :trending, -> { where("releasing_on >= ?", Time.now).order("clocks.size") }
 scope :trending, -> { joins(:clocks).where("releasing_on >= ?", Time.now).order("clocks.size") }
 scope :upcoming, -> { where("releasing_on >= ?", Time.now).order("releasing_on").order(:name) }
 scope :past, -> { where("releasing_on <= ?", Time.now).order("releasing_on desc").order(:name) }
 scope :tba, -> { where(releasing_on: nil).order(:name) }

 end

products_helper.rb

module ProductsHelper

def format_price(product)
  if product.tbd?
  "TBD"
  else
    number_to_currency(product.price)
  end
  end


def format_releasing_on(product)
  if product.tba?
  "TBA"
  else
      product.releasing_on
  end
  end

 def format_releasing_on_remaining(product)
   if product.tba?
      ""
    elsif product.out?
      "OUT"
    else
     (product.releasing_on - DateTime.now).to_i
  end
 end

end

产品 - index.html.erb

<header>

<div class="row">
<div class="span12 centered-pills">  

 <nav> 
  <ul class="nav nav-pills">
   <li><%= link_to 'Trending', filtered_products_path(:trending) %></li>
   <li><%= link_to 'Releasing Soon', filtered_products_path(:upcoming) %></li>
   <li><%= link_to 'Just Released', filtered_products_path(:past) %></li>
   <li><%= link_to 'TBA', filtered_products_path(:tba) %></li>
  </ul>
 </nav> 

</div>
</div>

</header>

clock.rb（时钟模型）

class Clock < ActiveRecord::Base
  belongs_to :product
  belongs_to :user
end

时钟表架构

  create_table "clocks", force: true do |t|
    t.integer  "product_id"
    t.integer  "user_id"
    t.datetime "created_at"
    t.datetime "updated_at"
  end

产品表架构

  create_table "products", force: true do |t|
    t.string   "name"
    t.text     "description"
    t.decimal  "price"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.date     "releasing_on"
    t.string   "website"
    t.string   "image_file_name"
    t.string   "industry"
    t.string   "slug"
    t.string   "image_content_type"
    t.integer  "image_file_size"
    t.datetime "image_updated_at"
    t.string   "company"
    t.integer  "total_clocks"
  end

SQL In Rails控制台失败：

2.0.0-p576 :037 > Product.joins(:clocks).where("releasing_on >= ?", Time.now).order("clocks.size")

  Product Load (0.3ms)  SELECT "products".* FROM "products" INNER JOIN "clocks" ON "clocks"."product_id" = "products"."id" WHERE (releasing_on >= '2014-11-07 18:55:15.595051') ORDER BY clocks.size
SQLite3::SQLException: no such column: clocks.size: SELECT "products".* FROM "products" INNER JOIN "clocks" ON "clocks"."product_id" = "products"."id" WHERE (releasing_on >= '2014-11-07 18:55:15.595051')  ORDER BY clocks.size

ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: clocks.size: SELECT "products".* FROM "products" INNER JOIN "clocks" ON "clocks"."product_id" = "products"."id" WHERE (releasing_on >= '2014-11-07 18:55:15.595051')  ORDER BY clocks.size

Answer 1

由于您希望按clocks排序，您必须在语句中加入该表，例如：

class Product < ActiveRecord::Base
  has_many :clocks  

  # ...
  scope :trending, -> { joins(:clocks).group("#{Product.table_name}.id").where("releasing_on >= ?", Time.now).order("count(clocks.product_id)") }
end

按大多数“趋势”（大多数时钟）轨道排序

1 个答案: