Eleven fields. One for each of the things that actually goes wrong when a multi-segment flight itinerary lives only inside a confirmation email buried under promotional newsletters.
The Date/Time start and Date/Time end fields are the ones that save the most grief. Not the approximate departure time you remember from booking, but the exact timestamp for each segment — which, on a three-leg itinerary, is the difference between making a connection with 45 minutes of buffer and arriving at a gate that closed eight minutes ago because your mental model had the departure at 14:55 and it was actually 14:35.
What the Record Contains
Flight number, seat reservation, and both datetime fields form the operational core. The seat reservation field is where you store the PNR and the specific seat assignment — 14A, not "window, near the front." On a codeshare with two flight numbers operating the same metal, the distinction matters for check-in and for reaching the airline's support line when something goes sideways.
Airline web page and Airline phone no. are the fields that become valuable at 11pm in a foreign airport after a mechanical cancellation. Not the airline website you'll eventually find after three minutes of phone typing under stress, but the direct link and the reservations number — already attached to the specific segment record.
Frequent flyer number is per-record because a multi-airline trip means different numbers for different carriers — Star Alliance, oneworld, and SkyTeam numbers don't transfer, and mileage credit to the wrong program on a partner flight is the kind of administrative error that wastes more time to fix than it's worth.
Notes is where the ground truth lives: the terminal-to-terminal connection that requires a specific shuttle and 40 minutes minimum despite the 90-minute layover shown on the booking; the airline that still needs a phone call to unlock premium seat selection despite a printed itinerary showing the seat already assigned; the lounge that's available on this card only via the specific terminal 2 entrance, not the main security-side entrance. That knowledge doesn't expire with one trip.