In Ruby/Rails, how to get current value of column of queried model in a different model class? -


i querying model within method in different model's class. how can refer queried model in sort of "rails way" preferably? please see code understand:

modela.where("id = ?", self.model_a_id).first.update_column(:attrbute_a, ???.attribute_a + self.attribute_b )

the "???" denotes how refer attribute model a. using self refer model b, class inside of.

you can way:

model = modela.find(model_a_id) model.update_column(:attribute_a, model.attribute_a + attribute_b)

btw, why don't use associations?


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