code: function getHoliday(db, date, callback) {
  
    // Check cache for Holiday
    let cacheKey = db.id + "-" + date;
    let cache = cache_holidayByDate.get(cacheKey);
    if ( cache !== null ) {
      return callback(null, cache);
    }
  
    // Build the select statement
    let select = "SELECT date, holiday_name, peak, service_info " +
      "FROM rt_holidays WHERE date=" + date;
  
    // Query the database
    db.get(select, function(err, result) {
  
      // Database Query Error
      if ( err ) {
        return callback(err);
      }
  
      // Holiday to return
      let holiday = undefined;
  
      // Holiday was found...
      if ( result !== undefined ) {
  
        // Build the Holiday
        holiday = new Holiday(
          result.date,
          result.holiday_name,
          result.peak === 1,
          result.service_info
        );
  
      }
  
      // Add holiday to cache
      cache_holidayByDate.put(cacheKey, holiday);
  
      // Return the holiday
      return callback(null, holiday);
  
    })
  
  }
docs: Get the Holiday for the specified date or 'undefined' if
  there is no holiday on the date
  
  @param {RightTrackDB} db The Right Track DB to query
  @param {int} date the date (yyyymmdd)
  @param {function} callback Callback function
  @param {Error} callback.error Database Query Error
  @param {Holiday} [callback.holiday] The selected Holiday