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.