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A Broken Data Model

By Steve Jones,

On one of my recent trips, there was a delay in leaving the gate. There were two passengers, both of whom had the same seat assignment on their boarding pass. You'd think there would be some sort of primary key that prevented this situation from occurring, but with the constant reassignment and movement of passengers at the gate, I can understand this happening. We print passes at a point in time, but since data can be revised, and new passes printed, there potentially would be a conflict.

However what came to light as we waited was both disconcerting and puzzling to me. The real problem was that one of the passengers was supposed to be on a later flight to the same city.

Apart from the security implications, it seems to me that the ability of someone to get through the scanner near the jetway with a boarding pass for the wrong flight implies a broken data model. I can only guess that the scanner is reading a passenger's name, destination, and seat number. Or that the flight data model is broken and there are two flights on the same day that share a flight number. The journey was short, so I suppose this airplane could have actually been making two round trips in a day.

I can't image the complexity and problems that programming an airline's flight system must bring to the data models and applications. With the constant shuffling of people, flights, and seats, I'm regularly surprised that it works smoothly most of the time. As my airline has modernized their systems, I'm even amazed at how much data they disclose on monitors to passengers waiting for upgrades or standby flights, and how quickly my mobile app updates with new data when there's a change.

I'd never experienced someone getting on the wrong flight before, and was surprised to find their software allowed it. However given that so much of the airline industry relies on systems that were developed decades ago, perhaps I shouldn't be surprised.

Steve Jones

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Steve Jones