전제

방법

컨트롤러

 def index
   @user = current_user
   @gear = Gear.where(user_id: @user.id)
 end

  def index
    @user = current_user
    @gear1 = Gear.where(user_id: @user.id, category: "住居系")
    @gear2 = Gear.where(user_id: @user.id, category: "料理系")
    @gear3 = Gear.where(user_id: @user.id, category: "火周り系")
    @gear4 = Gear.where(user_id: @user.id, category: "その他")
  end

보기

<div class="category bg-success">住居系</div>
  <% @gear1.each do |gear| %>
    <div class="gear-index-item mb-20">
      <% if gear.image.attached? %>
        <%= image_tag gear.image, class: "index-img" %>
      <% else %>
        <img class="index-img" src="<%= "/images/default_gear.jpg" %>" alt="Index image cap">
      <% end %>
      <%= link_to(gear.name, "/gears/#{gear.id}") %>
    </div>
  <% end %>

  <div class="category bg-warning">料理系</div>
  <% @gear2.each do |gear| %>
    <div class="gear-index-item mb-20">
      <% if gear.image.attached? %>
        <%= image_tag gear.image, class: "index-img" %>
      <% else %>
        <img class="index-img" src="<%= "/images/default_gear.jpg" %>" alt="Index image cap">
      <% end %>
      <%= link_to(gear.name, "/gears/#{gear.id}") %>
    </div>
  <% end %>
   .
   .
   .

결과

요약

where 메소드를 사용하면 간단하게 특정 컬럼으로 정리할 수 있다!