[RUBY] I want to distinct the duplicated data with has_many through

problem

For example, if there is a model of this kind of relationship

class User < ApplicationRecord
  has_many :lists
end

class List < ApplicationRecord
  belongs_to :user
  belongs_to :product
end

class Product < ApplicationRecord
  has_many :lists
end

User has multiple Lists, each List references Product ... I want to bring all the products related to User ...

Solutions

class User < ApplicationRecord
  has_many :lists

  #If this is the case, duplicate Products will be returned for the number of Lists.
  # has_many :products, through: :lists 

  #I'll insert a distinct
  has_many :products, ->{ distinct }, through: :lists
end

Very convenient (see [here] 1)

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