I have a presentation that I give from time to time with the title “Tackling Time Troubles – how Oracle handles datetime data” and in less than 10 days I will embark on a tour where I will deliver this presentation. One of the issues I talk about is how different nations handle daylight saving time changes and how much of a pain this can be. I did not anticipate this one though. As part of the MENA tour I will be flying with egypt air from Tunis through Cairo to Riyadh. Today, I received a very strange message from egyptair.
This has to do with the egyptians deciding on very short notice (1 week) that they want to re-introduce daylight saving time. And because they are already behind the date when everybody else in Europe advances their clocks, they chose _tomorrow_ (May 16th) to do so. This is potentially bad for a couple of reasons:
- it is very confusing if you need to coordinate meetings or phone calls across countries. The rest of the world would really like to know what time it is wherever you live
- computers that calculate these things have to be reprogrammed by people like me. This usually takes a while. My iPhone is giving me the wrong time. Oracle has a MOS note (1670704.1) about this but the latest timezone file patch does not yet include this change.
- schedules (for trains and flights) get all messed up during the switches. In the switch forward, trains will appear to arrive an hour late and on the switch back, they would really need two trains during the night (because there is one hour that “happens twice”. Or in the case of the Deutsche Bahn they simply stop all their trains in a station for one hour during the night. Either way it is madness.
- Flights to egypt from other countries will appear to arrive an hour later than what is written on the schedule
Egyptair is taking care of the latter one by simply delaying all departures by one hour:
The customers who issued their tickets before 23:59 Thursday 15th of May 2014:
The departure time will be one hour later than the time stated on the tickets.
While I do appreciate that I get to keep my comfy 1:45 of connection time, I also see this has a huge potential for chaos. If I look up the flight schedule on their website, both arrival and departure time are updated. But sites like flighttracker still show the old times, even for tomorrow. Also, if everybody in egypt simply advances their schedules by one hour, the effect of the DST change are nullified.
On top of all this, they seem to also have the idea of “suspending” DST during the islamic month of Ramadan. This would be between June 28th and July 27th in 2014. The IANA _guesses_ that these switches would actually happen on the 29th of June and 29th of July at midnight but no official word seems to exist.
Governments of this world: Would you please decide things with more than 7 days of notice? Preferrably 6 months or more so that we can comfortably and properly implement your ideas into the already very confusing hacks that keep track of all this timezone weirdness.