在Rails中进行联合搜索

问题描述

我正在Rails项目中进行简单的联合搜索。我要做的是根据用户在搜索框中输入的内容找到对项目的描述。我最常见的错误是：

Mysql2 :: Error：“ where子句”中的未知列“ item.description”：SELECT item_instances。* FROM item_instances内联接items ON items。{ {1}} = id。item_instances在item_id处。item ='服务器'

search.html.erb页面如下：

description

item_instances.rb（模型）文件

<p>
  Search results base on database field <span class='bold'><%= @columnType %></span> 
  with value: <span class='bold'><%= @search_value %> </span>
</p>

<p>Total Report Cost: <span class='bold'>$<%= @cost %><span></p>

<table class='reportTable'>
  <thead>
    <tr>
      <th class='reportTableHeaderCell'>Inv number</th>
      <th class='reportTableHeaderCell'>Description</th>
      <th class='reportTableHeaderCell'>Serial</th>
      <th class='reportTableHeaderCell'>PO number</th>
      <th class='reportTableHeaderCell'>PO date</th>
      <th class='reportTableHeaderCell'>Invoice</th>
      <th class='reportTableHeaderCell'>Date Out</th>
      <th class='reportTableHeaderCell'>Cost</th>
      <th class='reportTableHeaderCell'>Acro</th>
    </tr>
  </thead>

  <tbody>
    <% @item_instances.each do |item_instance| %>
      <tr class='searchTableRow'>
        <td class='reportTableCell'><%= link_to item_instance.inv_number,edit_item_instance_path(item_instance) %></td>
        <td class='reportTableCell'><%= item_instance.item.description %></td>
        <td class='reportTableCell'><%= item_instance.serial %></td>
        <td class='reportTableCell'><%= item_instance.po_number %></td>
        <td class='reportTableCell'><%= item_instance.po_date %></td>
        <td class='reportTableCell'><%= item_instance.invoice %></td>
        <td class='reportTableCell'><%= item_instance.date_out %></td>
        <td class='reportTableCell'><%= item_instance.cost %></td>
        <td class='reportTableCell'><%= item_instance.acro %></td>
      </tr>
    <% end %>
  </tbody>
</table>

项目模型：

class ItemInstance < ApplicationRecord
    validates :inv_number,:serial,:cost,presence: true
    belongs_to :item
    scope :in_order,->{order(:description)}
    

    # Named Scopes 
    scope :search_for_records_by_date,->(startDate,endDate) { where(date_out: startDate..endDate) }
    scope :search_for_records_by_column_and_value,->(columnName,value) { where("#{columnName}": "#{value}") }
    
    #I know something may be wrong in here. 
    scope :search_for_records_by_column_and_value_item_table,value) { where(item: "#{columnName}": "#{value}") }
    
end

item_instances控制器：

class Item < ApplicationRecord
    validates :description,:list_price,presence: true
    has_many :item_instances,dependent: :delete_all
    
    scope :in_order,->{order(:description)}
    scope :search_for_active_items,->(active) { where(active: active) }
    scope :search_for_records_by_column_and_value_on_items,value) { where("#{columnName}": "#{value}") }
end

路线文件：

class ItemInstancesController < ApplicationController

    def search 
     # Getting the params from what the user submitted 
     @columnType = params[:columnType]
     @search_value = params[:search_value]


     if @columnType == 'description'
      # SIMPLE THINGS I've TRIED:
      # @item_instances = ItemInstance.joins(:item).where(item: {description: "server"})
      #@item_instances = ItemInstance.joins(:items)
      #I TRIED THIS JUST TO SEE IF I COULD GET ANYTHING
      @item_instances = ItemInstance.joins(:item).where(:item => {description: "server"})

      #@item_instances = ItemInstance.joins(:item).search_for_records_by_column_and_value_item_table(@columnType,@search_value)
    end

    respond_to do |format| 
      format.html { render :search }
    end

  end 

end

schema.rb文件：

Rails.application.routes.draw do
  resources :item_instances
  get '/report',to: 'item_instances#report'
  get '/search',to: 'item_instances#search'

  resources :items
  get '/active',to: 'items#active'

  # Route to the home page 
  root 'item_instances#home'

end

请让我知道是否还有其他需要。我浏览了多篇文章和stackoverflow帖子都没有运气。任何有帮助的都会感激。

解决方法

在您的item_instances_controller.rb中，用where条件的项目替换item。在有条件的地方，必须指定完整的表名以进行比较。

class ItemInstancesController < ApplicationController

    def search 

    #yourcode
      @item_instances = ItemInstance.joins(:item).where(:items => {description: "server"})

    #yourcode

  end 

end