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问题描述
无论如何,我是否可以根据孩子返回的项目数来订购结果( ASC / DESC )模型(职位)?
Is there anyway I can order the results (ASC/DESC) by number of items returned from the child model (Jobs)?
@featured_companies = Company.joins(:jobs).group(Job.arel_table[:company_id]).order(Job.arel_table[:company_id].count).limit(10)例如:我需要在顶部打印最高职位的公司
For example: I need to print the Companies with highest jobs on top
推荐答案如果您希望经常使用此查询,建议您使用内置的 counter_cache
If you expect to use this query frequently, I suggest you to use built-in counter_cache
# Job Model class Job < ActiveRecord::Base belongs_to :company, counter_cache: true # ... end # add a migration add_column :company, :jobs_count, :integer, default: 0 # Company model class Company < ActiveRecord::Base scope :featured, order('jobs_count DESC') # ... end然后像这样使用它
@featured_company = Company.featured更多推荐
按has
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