Cutting decimals observer

observer.rb

def before_save(model)
  model.class.columns.each do |column|
    if column.type == :decimal
      int_part, frac_part = model.send(column.name).to_s.split(".")
      new_value = [int_part, frac_part[0...column.scale]].join(".")
      model.send("#{column.name}=", new_value)
    end
  end
end