Always, always declare your associations with symbols

Updated . Posted . Visible to the public. Deprecated.

This is not relevant for Rails 5.2+.

Never ever declare your associations with a string, especially when doing metaprogramming. A common mistake is something like

# WRONG
class Page < ActiveRecord::Base
  %w[main sub].each do |type|
    belongs_to "#{type}_title"
  end
end

   
# RIGHT
class Page < ActiveRecord::Base
  %w[main sub].each do |type|
    belongs_to :"#{type}_title"
  end
end

Always convert to a symbol, otherwise you'll have all kinds of fun.

Newer rails / activerecord (at least 5.2) will throw an association names must be a Symbol (ArgumentError) error if you define an association as string.

Tobias Kraze
makandra.de
Say thanks
Last edit
Michael Leimstädtner
Keywords
belongs_to, has_one, has_many
License
Source code in this card is licensed under the MIT License.

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