ruby-on-rails - Rails 3 参数错误 : Unknown key: begin_date

Question

我有一个 Waiver 对象，它有_many 个成员资格。我想弄清楚豁免是否具有给定季度的成员资格:

def has_current_membership?
  memberships.count("begin_date >= :begin_date AND end_date <= :end_date", { :begin_date => Time.now.beginning_of_quarter, :end_date => Time.now.end_of_quarter }).count > 0
end

然而，这给了我 ArgumentError: Unknown key: begin_date。但是，成员资格确实有一个 begin_date 列，因为如果我在控制台中执行 Waiver.first.memberships，我会得到:

[#<Membership id: 20, waiver_id: 1, begin_date: "2011-10-01", end_date: "2012-01-01", created_at: "2011-11-19 07:10:10", updated_at: "2011-11-19 07:10:10">] 

我做错了什么？

Answer 1

您应该使用 .where 作为查找条件，而不是 .count 两次:

memberships.where("begin_date >= :begin_date AND end_date <= :end_date", { :begin_date => Time.now.beginning_of_quarter, :end_date => Time.now.end_of_quarter }).count > 0