ruby-on-rails - 我如何探索 ActiveRecord 关系的结果？

Question

这就是我正在做的:

[72] pry(main)> Connection.joins(:inviter_memberships).where(inviter_memberships: { invited: c.inviter_membership.invited })
=> #<Connection::ActiveRecord_Relation:0x3fe19aa2ce28>

但不确定如何探索它以查看哪些记录适用于该关系。

我有一个 Connection 模型，它具有以下关联:

# == Schema Information
#
# Table name: connections
#
#  id                    :integer          not null, primary key
#  membership_id         :integer
#  invited_membership_id :integer
# truncated for brevity

class Connection < ActiveRecord::Base
  belongs_to :inviter_membership, class_name: "Membership", foreign_key: "membership_id"
  belongs_to :invited_membership, class_name: "Membership", foreign_key: "invited_membership_id"    
end

我有一个如下所示的Membership 模型:

class Membership < ActiveRecord::Base
  belongs_to :inviter, class_name: "User", foreign_key: "user_id"
  belongs_to :invited, class_name: "User", foreign_key: "invited_id"
  has_many :connections, dependent: :destroy
end

Answer 1

#<Connection::ActiveRecord_Relation:0x3fe19aa2ce28>表示您的查询有问题，更多信息 here

关于探索您的查询结果: 好吧，您可以通过两种方式查看，最简单的是添加 .all在您的查询结束时，另一个是在您的提示中执行以下操作

Connection.joins(:inviter_memberships).where(inviter_memberships: { invited: c.inviter_membership.invited }).each do |record|
  puts "---------"
  puts record
end

使用 first , second , third , last将向您显示您正在应用的查询然后您可以查看并调试您的查询有什么问题