Question

以下是＆＃34; Hotel＆＃34;的方法。用于查找关于事务和用户的top_spender的模型。

def top_spenders
    top_spenders = []
    self.transactions.group(:user_id).sum(:amount, :order => 'SUM(amount) DESC', :limit => 5).each do |record|
        person = User.find(record.first).name 
        amount = record.second
        person_amount = [person, amount]
        top_spenders << person_amount
    end 
    top_spenders
end

### hotel.rb
    has_many :transactions

### transaction.rb
    belongs_to :user
    belongs_to :hotel

提供弃用警告的行是：

self.transactions.group(:user_id).sum(:amount, :order => 'SUM(amount) DESC', :limit => 5)

弃用警告如下：

DEPRECATION WARNING: Relation#calculate with finder options is deprecated. Please build a scope and then call calculate on it instead. (called from top_spenders ...
DEPRECATION WARNING: The :distinct option for `Relation#count` is deprecated. Please use `Relation#distinct` instead. (eg. `relation.distinct.count`). (called from top_spenders ...

我确实尝试为分组事务添加范围，然后在其中查询sum，但警告仍然存在。此外，尝试了其他一些方法，但无法满足要求的弃用。

任何帮助都会受到很大的赞赏。

Answer 1

self.transactions.group("user_id").select("user_id, sum(amount) as total_amount").order("sum(amount) DESC").includes(:user)

这修复了弃用警告并启用了预先加载。感谢Rails 4. :)

Rails 4弃用警告：不推荐使用finder选项进行Relation＃calculate。请构建一个范围，然后在其上调用calculate

1 个答案: