Question

我使用此代码遇到了ActiveRecord 3.2.8的奇怪错误：

我有2个型号 - 客户和发票。

class Customer < ActiveRecord::Base
  has_many :invoices
end

class Invoice < ActiveRecord::Base
  belongs_to :customer

  def self.last(customer)
    customer.invoices.order("some_date_column DESC").first
  end
end

我正在运行类似的代码：

Thread.new do
  ActiveRecord::Base.connection_pool.with_connection do
    Customer.all.each do |customer|
      invoice = Invoice.last(customer)
      ...
    end
  end
end

运行该代码时，我有时会遇到以下奇怪错误：

/var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations/collection_association.rb:25:in 'initialize': wrong number of arguments (1 for 0) (ArgumentError)
from /var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations/collection_association.rb:25:in 'new'
from /var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations/collection_association.rb:25:in 'initialize'
from /var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations.rb:157:in 'new'
from /var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations.rb:157:in 'association'
from /var/lib/gems/1.8/gems/activerecord-3.2.8/lib/active_record/associations/builder/association.rb:44:in 'invoices'
from .../models/invoice.rb:7:in 'last'

非常感谢任何帮助。

Answer 1

当你遇到这种错误时

wrong number of arguments (X for Y)

这意味着您尝试调用传递的参数不同于预期的方法。在您的情况下，您调用的方法不应该接收任何参数（for 0），但您尝试传递一个（1 for）。从错误的最后一行开始，问题似乎是Invoice.last(customer)

Activerecord 3.2.8关联错误

1 个答案: