code: func GetUint64Setting(db *reform.DB, key string) (uint64, error) {
  	var setting Setting
  	err := db.FindByPrimaryKeyTo(&setting, key)
  	if err != nil {
  		if err == sql.ErrNoRows {
  			return 0, fmt.Errorf("key %s is not exist"+
  				" in Setting table", key)
  		}
  		return 0, err
  	}
  
  	value, err := strconv.ParseUint(setting.Value, 10, 64)
  	if err != nil {
  		return 0, fmt.Errorf("failed to parse %s setting: %v",
  			key, err)
  	}
  
  	return value, nil
  
  }
docs: // GetUint64Setting finds the key value in table Setting.
  // Checks that the value in the format of uint64