Time database: Difference between revisions
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| Provide time zone acronyms that are unique within each country and at any given point in time refer to only one offset from a base time | | Provide time zone acronyms that are unique within each country and at any given point in time refer to only one offset from a base time | ||
| Uses EST and CST for time stamps of zones in Australia that use DST and those that do not. That means for a given point in time during summer the offset from UTC and therefore UTC itself cannot be derived from the local time representation. | | Uses EST and CST for time stamps of zones in Australia that use DST and those that do not. That means for a given point in time during summer the offset from UTC and therefore UTC itself cannot be derived from the local time representation. | ||
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| ISO 3166-1 alpha-3 codes for countries | |||
| ISO 3166-1 alpha-2 codes for countries. Some of the codes have been re-assigned, e.g. CS can refer to Czechoslovakia or Serbia and Montenegro. | |||
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Revision as of 2013-09-20T19:58:10
Desired features:
| Time keeping database (tkdb) | IANA time zone database (tzdb) |
|---|---|
| Exactly one term for one kind of object | Uses terms interchangeably (region, zone), and uses ambiguous terms (zone for IANA zones and real world zones) |
| Provisional name for smallest geographic unit: "sector" | Smallest geographic unit is named "zone" |
| Stable boundaries of sectors, new sectors are created by splitting and deprecating old sectors, so users can know if they need to check their IDs for correctness. | /1/ user can link his computer to a tzid, but get's no notification if later his real location is in another zone, /2/ different locations are linked, e.g. Vaduz points to Zurich, Tel Aviv to Jerusalem |
| Record all legal time | /1/ no time for Bouvet Island, while Norwegian government has defined it, /2/ limited support for pre-1970 data |
| Provide time zone acronyms that are unique within each country and at any given point in time refer to only one offset from a base time | Uses EST and CST for time stamps of zones in Australia that use DST and those that do not. That means for a given point in time during summer the offset from UTC and therefore UTC itself cannot be derived from the local time representation. |
| ISO 3166-1 alpha-3 codes for countries | ISO 3166-1 alpha-2 codes for countries. Some of the codes have been re-assigned, e.g. CS can refer to Czechoslovakia or Serbia and Montenegro. |