2 ms·

How are time zones irrelevant? The current date, at this very moment, depends on the time zone. I think of date more like a date time simplified to day precisi

How are time zones irrelevant? The current date, at this very moment, depends on the time zone. I think of date more like a date time simplified to day precision. Still, I agree UTC date is unclear.

throwmeaway1212 4y ago
But if you have a date, and a timezone...how do you do anything useful with those 2 things? If you add 8 hours to a date due to PST, what do you get?
paulddraper 4y ago
As you say, timezones are relevant if you need to covert an instant to a date, or vice versa. But you can store, operate, and query on dates without the foggiest clue about instants or timezones.
spenczar5 4y ago
UTC isn’t a time zone, its a specification for how many seconds are in a day. In UTC, there are 84000 seconds on most days, but the IERS may announce a “leap second” which makes some particular day either 84001 seconds or 83999 seconds (historically always the former).
- nonethewiser 4y ago
  That was already clear
wodenokoto 4y ago
> How are time zones irrelevant? Nobody is going to adjust your birthdate when you move abroad. If you move east, you’ll be able to drink a little earlier than if you move west. Nobody is adjusting Christmas Eve against the time zone of Bethlehem. There are many situations where a date is just a number in a calendar and not a specific time on planet earth.
- nonethewiser 4y ago
  > Nobody is going to adjust your birthdate when you move abroad. But that’s just a convention, right? The day you are born is still dependent on the time zone. If you are born in the US at 11pm EST then someone born at that same moment in the UK has a different birthday. Dates have boundaries. These boundaries are dependent on time zone. We can talk about dates irrespective of time zone but day periods cannot be understood without reference to time zone.
  - throwmeaway1212 4y ago
    You are mixing two things up into one conversation. You are adding time into the conversation, in which case yes you need timezones, but if you don't add time into the conversation and just have dates, then you don't have timezones.
  - paulddraper 4y ago
    > But that’s just a convention, right? Yes, "just." Dates are "just" a convention.

How are time zones irrelevant? The current date, at this very moment, depends on the time zone. I think of date more like a date time simplified to day precision. Still, I agree UTC date is unclear.

throwmeaway1212 4y ago

But if you have a date, and a timezone...how do you do anything useful with those 2 things? If you add 8 hours to a date due to PST, what do you get?

paulddraper 4y ago

As you say, timezones are relevant if you need to covert an instant to a date, or vice versa. But you can store, operate, and query on dates without the foggiest clue about instants or timezones.

spenczar5 4y ago

UTC isn’t a time zone, its a specification for how many seconds are in a day. In UTC, there are 84000 seconds on most days, but the IERS may announce a “leap second” which makes some particular day either 84001 seconds or 83999 seconds (historically always the former).

nonethewiser 4y ago
That was already clear

wodenokoto 4y ago

> How are time zones irrelevant? Nobody is going to adjust your birthdate when you move abroad. If you move east, you’ll be able to drink a little earlier than if you move west. Nobody is adjusting Christmas Eve against the time zone of Bethlehem. There are many situations where a date is just a number in a calendar and not a specific time on planet earth.

nonethewiser 4y ago
> Nobody is going to adjust your birthdate when you move abroad. But that’s just a convention, right? The day you are born is still dependent on the time zone. If you are born in the US at 11pm EST then someone born at that same moment in the UK has a different birthday. Dates have boundaries. These boundaries are dependent on time zone. We can talk about dates irrespective of time zone but day periods cannot be understood without reference to time zone.
- throwmeaway1212 4y ago
  You are mixing two things up into one conversation. You are adding time into the conversation, in which case yes you need timezones, but if you don't add time into the conversation and just have dates, then you don't have timezones.
- paulddraper 4y ago
  > But that’s just a convention, right? Yes, "just." Dates are "just" a convention.