CODEWITHSUNDEEP
ruby-on-railsrubyactiverecord
Kaia
Kaia

Reputation: 891

Rails ActiveRecord get value from column, or from association's default if nil

I'm sure this has been answered, but my searching is failing me.

I have two models:

class Person < ApplicationRecord
    belongs_to :family
    # has column "last_name"
end

class Family < ApplicationRecord
    has_many :people
    # has column "last_name"
end

I would like Person.take.last_name to:

I could do something like

class Person < ApplicationRecord
    belongs_to :family
    # has column "last_name"

    def last_name_lookup
        last_name || family&.last_name || nil
    end
end

But was wondering if there is a built-in rails way to do this, or if it's considered improper to mask a column's true value.

Upvotes: 0

Views: 550

Answers (1)

Les Nightingill
Les Nightingill

Reputation: 6156

I don't know of a Rails built-in way. But you can do

# in person.rb

def last_name # yes, overrides the built-in getter
  read_attribute(:last_name) || family&.last_name # will be nil if both last_names are nil
end

Upvotes: 1

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