def type_cast_code(var_name)
case type
when :string then nil
when :text then nil
when :integer then "#{var_name}.to_i rescue #{var_name} ? 1 : 0"
when :float then "#{var_name}.to_f"
when :decimal then "#{self.class.name}.value_to_decimal(#{var_name})"
when :datetime, :timestamp then "#{var_name}.class == Time ? #{var_name} : #{self.class.name}.string_to_time(#{var_name})"
when :time then "#{var_name}.class == Time ? #{var_name} : #{self.class.name}.string_to_dummy_time(#{var_name})"
when :date then "#{var_name}.class == Date ? #{var_name} : #{self.class.name}.string_to_date(#{var_name})"
when :binary then nil
when :boolean then "#{self.class.name}.value_to_boolean(#{var_name})"
else nil
end
end