2 ms·

You should definitely use geographic timezone like America/Los_Angeles instead of just offset. Offset actually isn't a real timezone it is just an offset. Timez

You should definitely use geographic timezone like America/Los_Angeles instead of just offset. Offset actually isn't a real timezone it is just an offset. Timezone usually means a lookup table of what offset it has at what time and that can also change due to different laws at different time. So I assume the moment EU countries will change the rules there will be one more row for each timezone that will say "from this time the offset is such and such". That means it is also important to use the right timezone in the sense that even though Bratislava/SK and Prague/CZ have the same rules (DST time and offsets) at the moment they can change in different ways after the DST is removed (as whether to use winter or summer time afterwards is in jurisdiction of each country I think).

pmontra 8y ago
I agree. In the only project I worked on where time was really important I stored a triple (original datetime, UTC timestamp, original time zone). I used UTC to globally sort events and sent the original datetime back to clients for display. On the other side, sometimes we don't know where an event happens. Think of GPS trackers close to a border which is also a timezone border. This is a more complex problem which requires at least a model of country borders and maybe roads. Finally, on some systems I'm using as a user, they have some EU timezones but not even all the major countries. It doesn't matter now but it will. I expect they'll add the missing timezones and make us confirm where we are.