類似檢索項的索引在陣列 - Aggregation: add option to $unwind to emit array index - Get index of an item within mongodb query 我有這樣的用例。 最美味的水果排名： {"date": "Jan 1st",
"fruit_ranking": ["Apple", "Orange", "Grape", "
給出一個簡單的嵌入式關係的擴展名是這樣的： class D
include Mongoid::Document
embeds_many :es do
def m
#...
end
end
end
class E
include Mongoid::Document
embedded_in :d
end
你可
谷歌對此不是很友好。 我有一個服務模型，它也保存了與類別模型的關係。 class Service
include Mongoid::Document
has_and_belongs_to_many :categories, inverse_of: :service
end
class Category
include Mongoid::Document