html - Rails 4 - 由于关联，渲染 View 很慢

Question

我有这个问题:

  @companies = Company.includes(:car, :member).where('companies.status != 3 AND companies.status != 4 AND companies.status != 5').order(sort_column + " " + sort_direction) 

观点:all_companies.html.erb:

  <div id="cars_list">
    <%= render :partial => 'companies_list', locals: { companies: @companies } %>
  </div>

_companies_list.html.erb:

<div class="tr">
  <span class="td">ID</span>
  <span class="td">Registration</span>
  ...
</div>
<% companies.each do |company| %>
  <%= form_tag edit_inline_company_path(:id => company.id), :method => "post", :id => "id#{company.id}", :remote => true do %>
    <%= render :partial => 'edit_inline_company', locals: { company: company } %>
  <% end %>
<% end %>

_edit_inline_company.html.erb:

<span class="td">
  <span class="td">
    <%= company.id %>     
  </span>
  <span class="td">
    <%= company.location %>     
  </span>
  <span class="td">
    <%= company.registered_at %>     
  </span>
  ...
  <span class="td">
    <%= company.member.full_name %>     
  </span>
  <span class="td">
    <%= company.car.code %>     
  </span>
  <span class="td">
    <%= company.car.driver %>     
  </span>
  ...
</span>

问题 - View 需要 1800 毫秒来呈现(只有大约 40-50 个项目要显示)。

我在查询中添加了.includes(:car, :member)来避免N+1问题(但实际上，它根本不影响速度)。

经过一些调试，我试图从 _edit_inline_company.html.erb 中删除与不同模型相关的项目:

  <span class="td">
    <%= company.member.full_name %>     
  </span>
  <span class="td">
    <%= company.car.code %>     
  </span>
  <span class="td">
    <%= company.car.driver %>     
  </span>

渲染数据所需的时间大约下降了。 700 毫秒，但是，我在输出中也需要这些字段。

如何优化呢？我可能忽略了什么？

提前谢谢你。

编辑:

我尝试按照@brenzy 的建议添加索引，如下所示:

add_index :companies, :car_id, :name => 'car_id_ix'
add_index :companies, :member_id, :name => 'memberr_id_ix'

+ rake db:migrate，但加载时间保持不变，这里没有加速。

Answer 1

尝试为您的联想建立索引。这是一个可能有用的链接:https://tomafro.net/2009/08/using-indexes-in-rails-index-your-associations