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我有兩個模型ObjectA和ObjectB。 ObjectB有兩列,a_1_id和a_2_id,它們都是ObjectA的外鍵。 ObjectB屬於這些外部ObjectA對象的每一個。如何設置一個模型屬於另一個模型的兩個實例的Rails關聯?
class ObjectA < ActiveRecord::Base
attr_accessible :player_1, :player_2, :subject, :turn
belongs_to :player_1, :class_name => "User"
belongs_to :player_2, :class_name => "User"
has_many :object_b, dependent: :destroy, :finder_sql => "SELECT * FROM object_bs where (a_1_id = #{id} or a_2_id = #{id})"
end
class ObjectB < ActiveRecord::Base
attr_accessible :a_1_id, :a_2_id
belongs_to :a_1_id, :class_name => "ObjectA"
belongs_to :a_2_id, :class_name => "ObjectA"
end
這是設置關聯的最佳方式嗎?
我認爲Rails的可確定通過簡單地追加_id給定的名稱。情況並非如此嗎? – Quentamia
當您聲明'belongs_to:player_1'時,它假定有一個Player1類並查找關鍵字'player1_id'。當你指定':class_name =>'User''時,它會查找關鍵字'user_id'。 – tybro0103
如果我添加外鍵,在嘗試刪除ObjectA實例時仍然收到以下錯誤:SQLite3 :: SQLException:no such column:object_bs.object_a_id:SELECT「object_bs」。* FROM「object_bs」WHERE「object_bs」 。「object_a_id」= 4 – Quentamia