ruby on rails - Mongoid Query Related Collection -


i'm trying figure out how query related collections in mongoid.

here object model (simplified brevity):

category ------------------- class category     include mongoid::document      field :name, type: string     ...     belongs_to: product end  class product    include mongoid::document     field :name, type: string    ...    has_one :category end

i'm trying build query products category particular name e.g. "toy"

products = product.where('category.name' => 'toy')

i nil collection back. think mongoid not support types of queries directly. how build query accomplish that?

try following

category = category.find_by(name: 'toy') # following work products = product.where(category: category) products = product.where(category_id: category.id)

this work, but it's not recommended use mongoid way

mongoid provides relational-style associations convenience application developers used dealing relational databases, not recommend use these extensively.


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