MySQL ORDER BY multiple elements in different where clauses - mysql

Question

I have a question for which I do not know how exactly to call it. Maybe I just don't use the correct naming and therefore I cannot find the answer.
But the case is like this.
I have a database table with similair data to the following:
booking_id (int)
booking_start (Y-m-d)
booking_starttime (H:i)
booking_hotelstart (Y-m-d)
booking_hotelstarttime (Y-m-d)
booking_hotelend (Y-m-d)
booking_hotelendtime (H:i)
booking_end (Y-m-d)
booking_endtime (H:i)
booking_confirmed (bool)
Now I would like to make a query that does about this :
(invalid query just to demonstrate what I would like)
SELECT `booking_id` FROM `system_bookings` WHERE (
(`booking_start`='2014-10-20' ORDER BY `booking_starttime` ASC)
OR
(`booking_hotelstart`='2014-10-20' ORDER BY `booking_hotelstarttime` ASC)
OR
(`booking_hotelend`='2014-10-20' ORDER BY `booking_endtime` ASC)
OR
(`booking_end`='2014-10-20' ORDER BY `booking_endtime` ASC)
)
AND
`booking_confirmed` = TRUE LIMIT 0, 100
So basically an ORDER BY with a clause. But how to do this?? I have no clue how to correctly search for this. Hence I hope someone could show me a bit the direction I should be heading. Other than that. I would like to know how this is called. For next searches.
Thanx in advance!!!
edit :
I created some sample data as requested :
CREATE TABLE IF NOT EXISTS `system_bookings` (
`booking_id` int(6) NOT NULL AUTO_INCREMENT,
`booking_start` date NOT NULL,
`booking_starttime` varchar(5) NOT NULL,
`booking_hotelstart` date NOT NULL,
`booking_hotelstarttime` varchar(5) NOT NULL,
`booking_hotelend` date NOT NULL,
`booking_hotelendtime` varchar(5) NOT NULL,
`booking_end` date NOT NULL,
`booking_endtime` varchar(5) NOT NULL,
`booking_confirmed` tinyint(1) NOT NULL,
PRIMARY KEY (`booking_id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=6 ;
INSERT INTO `system_bookings` (`booking_id`, `booking_start`, `booking_starttime`, `booking_hotelstart`, `booking_hotelstarttime`, `booking_hotelend`, `booking_hotelendtime`, `booking_end`, `booking_endtime`, `booking_confirmed`) VALUES
(1, '2014-10-09', '21:19', '2014-10-08', '21:19', '2014-10-23', '08:00', '2014-10-23', '22:00', 1),
(2, '2014-10-11', '16:00', '2014-10-27', '12:15', '2014-10-28', '17:45', '2014-10-28', '17:45', 1),
(3, '2014-10-10', '20:30', '2014-10-10', '20:30', '2014-10-11', '08:00', '2014-10-20', '14:00', 1),
(4, '2014-10-12', '20:00', '2014-10-12', '20:00', '2014-10-13', '05:00', '2014-10-29', '22:00', 0),
(5, '2014-10-22', '15:00', '2014-10-22', '20:30', '2014-10-23', '04:15', '2014-10-31', '12:00', 1);

Answer 1

You can have multiple conditions in the order by clause. So, formally, you seem to want this:
SELECT `booking_id`
FROM `system_bookings`
WHERE `booking_confirmed` = TRUE AND
(`booking_start` = '2014-10-20' OR
`booking_hotelstart` = '2014-10-20' OR
`booking_hotelend`='2014-10-20' OR
`booking_end`='2014-10-20'
)
ORDER BY (CASE WHEN `booking_start` = '2014-10-20' THEN `booking_starttime`
WHEN `booking_hotelstart` = '2014-10-20' THEN `booking_hotelstarttime`
WHEN `booking_hotelend` = '2014-10-20' THEN `booking_endtime`
WHEN `booking_end` = '2014-10-20' THEN `booking_endtime`
END)
LIMIT 0, 100;
However, this is a bit non-sensical, because you are comparing a value to a constant, and then sorting by that value. I suspect you want to prioritize the where clauses and really want something more like this:
ORDER BY (CASE WHEN `booking_start` = '2014-10-20' THEN 1
WHEN `booking_hotelstart` = '2014-10-20' THEN 2
WHEN `booking_hotelend` = '2014-10-20' THEN 3
WHEN `booking_end` = '2014-10-20' THEN 4
END)