3

这是我的控制器（索引已排序）：

  def index
    if params[:limit]
      @bisacs = Bisac.order(:bisac_code).page(params[:page]).per(params[:limit])
    else
      @bisacs = Bisac.order(:bisac_code).page(params[:page])
    end
  end

以下是执行的查询（我认为太多且太慢，第一页需要 6-7 秒或导航到下一个/最后一个：

Started GET "/bisacs" for 127.0.0.1 at 2015-08-11 13:16:33 -0400
Processing by BisacsController#index as HTML
  Rendered home/_main_links.html.erb (0.2ms)
 CYPHER 358ms MATCH (result_bisac:`Bisac`) RETURN count(result_bisac) AS result_bisac 
 CYPHER 389ms MATCH (result_bisac:`Bisac`) RETURN result_bisac ORDER BY result_bisac.bisac_code SKIP {skip_0} LIMIT {limit_25} | {:skip_0=>0, :limit_25=>25}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319299}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319299}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320808}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320808}
 CYPHER 120ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319262}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319262}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320349}
 CYPHER 120ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320349}
 CYPHER 120ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318456}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318456}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320054}
 CYPHER 116ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320054}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321703}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321703}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319503}
 CYPHER 117ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319503}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321755}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321755}
 CYPHER 116ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319313}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319313}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321376}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321376}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321021}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321021}
 CYPHER 123ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319280}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319280}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318845}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318845}
 CYPHER 122ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320822}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320822}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318841}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318841}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321956}
 CYPHER 117ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24321956}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319031}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319031}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320070}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320070}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24322195}
 CYPHER 116ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24322195}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319124}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319124}
 CYPHER 119ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24322258}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24322258}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318767}
 CYPHER 121ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24318767}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320583}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24320583}
 CYPHER 118ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319086}
 CYPHER 117ms MATCH n WHERE (ID(n) = {ID_n}) WITH n RETURN ID(n) | {:ID_n=>24319086}
  Rendered bisacs/index.html.erb within layouts/application (6722.1ms)
Completed 200 OK in 7096ms (Views: 7095.5ms)

如何改进？为什么这 25 个节点会被一个一个地取出来？

在 Neo4j 控制台中检索所有 3983 个代码只需要 1 秒左右：

MATCH (result_bisac:`Bisac`) RETURN result_bisac ORDER BY result_bisac.bisac_code;
Returned 3983 rows in 1064 ms, displaying first 1000 rows.
4

2 回答 2

3

嗯，好的，所以这是另一个有点尴尬的答案；）

如果您将以下内容放入您的配置中（在config/environments/development.rb或中config/application.rb），它应该修复它：

config.neo4j._active_record_destroyed_behavior = true

说明： gem 实现的方法与ActiveNode#exists?方法有点不同ActiveRecord#exists?。在 ActiveRecord 中，它只是检查对象是否在内存中的某个时间点被销毁。在 ActiveNode 中，我们正在检查实际的数据库（也许我们在某些时候需要查询缓存）。

所以，长话短说，我们不想马上引入这个变化，因为它是一个破坏性的变化，所以我放入了一个配置变量来修复它。6.0 版中不需要配置变量

于 2015-08-11T18:10:19.443 回答
0

我在视图中的标签中注释了以下前 3 行，速度变得可以接受，大约一秒钟：

<% @bisacs.each do |bisac| %>
  <tr>
    <td><%#= link_to 'Show', bisac %></td>
    <td><%#= link_to 'Edit', edit_bisac_path(bisac) %></td>
    <td><%#= link_to 'Destroy', bisac, method: :delete, data: { confirm: 'Are you sure?' } %></td>
    <td><%= bisac.bisac_code%></td>
    <td><%= bisac.bisac_value%></td>
  </tr>
<% end %>

然而，添加一个返回“show”的链接会使页面渲染再次变得非常缓慢：

<% @bisacs.each do |bisac| %>
  <tr>
    <td><%= link_to bisac.bisac_code, bisac%></td>
    <td><%= bisac.bisac_value%></td>
  </tr>
<% end %>
于 2015-08-11T17:49:24.777 回答