是的有可能
首先在模型中定义ransacker和ransackable_attributes

ransacker :unit_price do |parent|
  # Functionality of your method using Arel
  parent.table[:price_cents] / parent.table[:quantity_by_pack]
end

def self.ransackable_attributes(auth_object = nil)
  # You can use something like:
  # attrs = super
  # attrs += ['unit_price']

  # But it will be deprecated so it's better to use such method:
  authorizable_ransackable_attributes
end

在那之后，

search = Ingredient.ransack({})
search.sorts = 'unit_price asc'

search.result
# Return Active Record relation with SQL query:
# SELECT "ingredients".* FROM "ingredients"
# ORDER BY "ingredients"."price_cents" / "ingredients"."quantity_by_pack" ASC

或

search = Ingredient.ransack({})
search.sorts = 'unit_price desc'

search.result
# Return Active Record relation with SQL query:
# SELECT "ingredients".* FROM "ingredients"
# ORDER BY "ingredients"."price_cents" / "ingredients"."quantity_by_pack" DESC