There's somebody in my seat (again)

Sometimes it just pays off that airlines are stuck in the middle-ages. IT-wise, that is. Of course, there are other times, when it annoys the hell out of me. Here is why:

On my return flight from Johannesburg a few days ago, it happened again: I board the plane, find my seat (3G) and there is a guy already sitting there, shoes off, a gazillion newspaper scattered around him. I ask him, whether he's in the correct seat, and yes, his boarding pass sure reads 3G also. So I find the flight attendant, explain to her the situation, she radios the gate agent, and 2 minutes later, I'm asked to go upstairs (it's a 747) and I find myself in First Class. Nice, particularly on an 11-hour flight.

Now, I won't be describing all the food and wine, I'm a techie after all, and slept through most of the flight anyway. What interests me is, how it is possible to create double-bookings to begin with. Apparently, airline systems are still unable to use current technology to avoid those situations. I would imagine that there is a booking system that has records for flights (on a particular day), aircrafts, class of service, seats, passengers, meals, etc. and that data model does not look particularly difficult. Of course, lots of foreign key relationships between those entities, but the seat number in any particular aircraft should be pretty unique. Unless some clown actually put two physical seats with 21C ... ah, never mind. Wouldn't happen. It's in fact more likely that there are seat numbers missing than there are duplicates. Lufthansa aircrafts, for example, never have a row 13.

Back to those airline systems. Even if we assume that there are multiple distributed databases that hold reservations, bookings, check-ins, and the like, someone should tell the airlines that there is something like two-phase commit, which has actually been around since the 80s. So even if there were two agents trying to book conflicting (i.e., duplicate seat assignement) records, it just shouldn't happen. But it does. Well, as long as I get upgraded every time, I'm actually happy that airline IT is still in the middle-ages. Now, if the airlines would finally get their act together and credit all my flights into my frequent flier account. But that's a different story.