 		`name` VARCHAR(128) NOT NULL,
 		`col_name` VARCHAR(64) NOT NULL COLLATE `UTF8_GENERAL_CI`,
 		`type_name` VARCHAR(64) NOT NULL,
+		`is_nullable` BOOLEAN NOT NULL DEFAULT FALSE,
 		`ref_type_id` INT DEFAULT NULL,
 		`is_list` BOOLEAN NOT NULL DEFAULT FALSE,
 		`compare_options` ENUM (

		OPEN fields_cur;

		FETCH fields_cur
		INTO cf_id, cf_col_name, cf_type_name, cf_ref_type_id,
			cf_is_list, cf_compare_options;
		WHILE NOT fields_done DO
			CALL _update_type_fields_def_constr(
				fields_defs, fields_constraints, inheriting,
				c_type_id, cf_id, cf_col_name, cf_type_name, cf_ref_type_id,
				cf_is_list, cf_compare_options
			);
			FETCH fields_cur
			INTO cf_id, cf_col_name, cf_type_name, cf_ref_type_id,
				cf_is_list, cf_compare_options;
		END WHILE;
	END;

	DELETE FROM `nz_admin_db`.`field_shadow`;
	CALL QEXEC(CONCAT(
		"INSERT INTO `nz_admin_db`.`field_shadow`
		(`id`, `owner_type_name`, `owner_type_id`, `name`, `col_name`, `type_name`, `is_nullable`, `ref_type_id`, `is_list`, `compare_options`, `back_ref_name`, `back_ref_id`)
		SELECT `id`, `owner_type_name`, `owner_type_id`, `name`, `col_name`, `type_name`, `is_nullable`, `ref_type_id`, `is_list`, `compare_options`, `back_ref_name`, `back_ref_id`
		FROM `", source_db_name, "`.`field`;"
	));
END //
