Question

Rails 4.2.1 Ruby 2.0.0

我希望将postgres数组计数查询的结果显示为rails视图中的简单表。该表应该有2列;部署和统计。

我可以使用以下SQL

成功查询postgres

select unnest(deployed), count(deployed) from current_customer_profiles group by current_customer_profiles.deployed;

postgres查询的结果是

deployed | count

on prem  | 4

saas     | 2

我尝试在rails中使用select_rows和find_by_sql：

@deployment = CurrentCustomerProfile.connection.select_rows('select unnest(deployed) as deployed, count(deployed) as count from current_customer_profiles group by current_customer_profiles.deployed')

@deployment = CurrentCustomerProfile.find_by_sql(%q{select unnest(deployed) as deployed, count(deployed) as count from current_customer_profiles group by current_customer_profiles.deployed})

我尝试了许多不同的方法来将数据显示为rails视图中的简单表格。

我遇到的问题是：

字符串（部署列）在视图中显示为[]而不是值（有趣的是，计数显示正常，因此结果如下; [] 4和[] 2）
结果以部署列和计数的字符串形式返回，即“on prem 4”而不是两列，on the，4

以下是我尝试的两个视图示例（按上述两项的相应顺序）：

<% @deployment.each do |e| %>
    <%= e.deployed %> <%= e.count %>
<% end %>


<% @deployment.each do |b| %>
    <% b.each do |bb| %>
     <%= bb %>
        <% end %>
<% end %>

如何在rails视图的表格中显示postgres数组中项目计数的结果？这是我关于堆栈溢出的第一篇文章，所以如果我应该提供更多信息，请告诉我。

Answer 1

我能够将这种方法用于哈希结果

<% @deployment.each do |key, value| %>
  <%= key %> <%= value %>
<% end %>

Answer 2

Count是一个属性，请尝试

 <% @deployment.each do |e| %>
   <%= e['deployed'] %> <%= e['count'] %>
 <% end %>

Answer 3

当查询返回哈希值时，你必须像这样做

 <% @deployment.each do |e| %>
   <%= e['deployed'] %> <%= e['count'] %>
 <% end %>

rails，无法在视图中显示postgres数组计数结果

3 个答案: