ruby-on-rails - rails 列表记录属性，如 x

Question

例如，我有 4 条账单记录。

id    = 1 
prize = 100
city  = "newyork"

id    = 2
prize = 200
city  = "NEWYORK"

id    = 3 
prize = 300
city  = "Boston"

id    = 4
prize = 400
city  = "BOSTON"

我想获得带有哈希值的城市的统计数据{"Newyork" => 2 , "Boston" => 2 }

Answer 1

your_collection.group_by(&:city)