我有2个模型:Rails ActiveRecord Association问题
Performance和PerformanceType以及2个相应的表格:performance和performance_types。
表演中有一个外键列“performance_type_id”。
如何使用ActiveRecord关联从另一个表中获取performance_type_id的名称?
class Performance < ActiveRecord::Base
has_one :users
has_one :rates
has_one :performace_types
end
class PerformanceType < ActiveRecord::Base
belongs_to :performances
end
有了上面的代码我尝试做的到控制台:
myvar = Performance.first
myvar.performance_types
NoMethodError: undefined method `performance_types' for #<Performance:0x007f9694b3e700>
我知道这个问题是我的活动记录协会的不好解释,谁能帮助我?
关于。
从创建到外键添加迁移...
class CreatePerformances < ActiveRecord::Migration
def change
create_table :performances do |t|
t.timestamps null: false
end
end
end
class CreatePerformanceTypes < ActiveRecord::Migration
def change
create_table :performance_types do |t|
t.timestamps null: false
end
end
end
class AddPerformanceTypeIdToPerformance < ActiveRecord::Migration
def change
add_column :performances, :performance_type_id, :integer
end
end
class AddAppointmentInfoToPerformance < ActiveRecord::Migration
def change
add_column :performances, :user_id, :integer
add_column :performances, :start_at, :datetime
add_column :performances, :end_at, :datetime
end
end
class AddUserToPerformances < ActiveRecord::Migration
def change
add_foreign_key :performances, :users
end
end
class AddTypeToPerformances < ActiveRecord::Migration
def change
add_foreign_key :performances, :performance_types
end
end
class AddAdditionalFieldsToPerformanceType < ActiveRecord::Migration
def change
add_column :performance_types, :name, :string
add_column :performance_types, :description, :string
end
end
class AddPerformanceTypeToRate < ActiveRecord::Migration
def change
add_foreign_key :rates, :performance_types
end
end
class AddRateToPerformances < ActiveRecord::Migration
def change
add_column :performances, :rate_id, :integer
add_foreign_key :performances, :rates
end
end
它应该是单数,而不是复数。 'has_one:performance_type'你也拼错表现 - 可能只是输入你的问题时, –