ruby on rails -我应该在helper中做这个吗?还是会变慢

Question

在这种情况下，哪种模式会更快?
显然，Pattern1 with helper看起来更复杂，看起来更干净。但是每次调用user_link方法时，它都会发送SQL。
在这里，它在一个页面加载时调用多达100次。

哪种方式对基准性能更好?

Pattern1。与辅助

application_helper

def user_link(username)
    link_to User.find_by_username(username).user_profile.nickname, show_user_path(username)
end

视图

<% @topics.order("updated_at DESC").limit(100).each do |topic| %>
    <%= user_link(topic.comment_threads.order("id").last.user.username) if topic.comment_threads.present? %>
<% end %>

Pattern2。没有帮手。仅查看

<% @topics.order("updated_at DESC").limit(100).each do |topic| %>
    <%= link_to(topic.comment_threads.order("id").last.user.nickname, show_user_path(topic.comment_threads.order("id").last.user.username) ) if topic.comment_threads.present? %>
<% end %>

Answer 1

try

# Topics model
#via scope
scope :get_topic_list, lambda do
  order("updated_at DESC").joins(:comment_threads => :user).limit(100)
end
#via method
def self.get_topic_list
  Topic.order("updated_at DESC").joins(:comment_threads => :user).limit(100)
end
# in your controller or move to model itself (recommened)
@topics = Topic.get_topic_list
# in you view
<% @topics.each do |topic| %>
    <%= link_to(topic.comment_threads.order("id").last.user.nickname, show_user_path(topic.comment_threads.order("id").last.user.username) ) if topic.comment_threads.present? %>
<% end %>