tags : Human Computer Interaction ( HCI ), Database, Clocks

This is interesting to me, notations and ways to represent date and time

There’s something called metric time

Resources

Different ways to show

Calendar

Clock

Date, Time and Timezone

Meta

  • data : Doesn’t have a time component but what actual point-in-time it is really is determined by the reader of the data(where they live)
  • date/time : Same as date. The correct time is determined by what timezone your location is assigned to.
    • date/time by itself doesn’t seem

What to go with?

point-in-time datainterop btwn systemsdifferent systems opssortable
unix timestampYESYESYESYES
date time w tzYES + tz origin dataNo, needs logicYESYES
date time w/o tzNo, represent social time

Which timezone to pick? (If you picked date time w tz)

  • If you just want date and don’t want time component, UTC+000 seems like a way to go.
  • If you need to know the original timezone of the event, then store it with the original timezone.
  • Unless you have a reason to store something in a local timezone, UTC is the right choice, but no choice is perfect.
  • If using pg, use:

More on unix timestamp (from some article)

  • Common misconception is that Unix time can’t be used to represent dates before January 1st, 1970.
    • It is timezone agnostoc works across timezones
  • Unlike Unix timestamp, there is no such thing as a universal DateTime format. Each programming language or tool relies on its own internal logic and implementation details for this data type. For the purpose of this article, we’ll categorize DateTime as an embedded calendar-aware and timezone-aware module, capable of handling the complexity of modern time-keeping systems.

Resources