I have this in a model: class GenreBadge < ActiveRecord::Base
belongs_to :game, counter_cache: :genre_badges_count, touch: true belongs_to :genre validates :game_id, uniqueness: {scope: :genre_id}, allow_blank: true
end
When I get one existing genre badge genre_badge = game.genre_badges.first genre_badge.game_id = nil genre_badge.save!
It creates an validation exception: "ActiveRecord::RecordInvalid: Validation failed: Game has already been taken"
I already have have specified that I want to allow_blank. I really don't know why I get the validation error. I also tested allow_nil but got the same error.