instance method read_value_from_parameter

# File activerecord/lib/active_record/base.rb, line 2046
      def read_value_from_parameter(name, values_hash_from_param)
        klass = (self.class.reflect_on_aggregation(name.to_sym) || column_for_attribute(name)).klass
        if values_hash_from_param.values.all?{|v|v.nil?}
          nil
        elsif klass == Time
          read_time_parameter_value(name, values_hash_from_param)
        elsif klass == Date
          read_date_parameter_value(name, values_hash_from_param)
        else
          read_other_parameter_value(klass, name, values_hash_from_param)
        end
      end