Talk:List of tz database time zones/Archive 2020

Generating the table

How is the time zone table generated? Is there some program that does it? Groogle (talk) 01:55, 7 December 2018 (UTC)

Groogle, do you mean the table in the article? It looks like people are just editing it manually. I agree it would be much better if it was generated from the tz database. Stephen (talk) 03:40, 24 March 2020 (UTC)

The country code, latitude/longitude, TZ database name, and portion of country covered columns could come from the zone.tab file (the "portion of country covered" could come from the "comments" column in that file). The "tz database name" column would be used to look up a tzdb entry in the source files; if it's a Link entry, the status column would either be "Alias" or "Deprecated" - "Deprecated" if it's in the "backward" file, "link" otherwise - and if it's not a "Link" entry, it'd be "Canonical". The UTC offset columns would come from the most recent entry in the Zone item for the zone.

I don't know whether anybody's written a script to do that. Guy Harris (talk) 09:36, 24 March 2020 (UTC)

DST in Africa/Ceuta

According to 2017c, time zone Africa/Ceuta observes EU DST, moving from +0100 to +0200. This should be fixed in this page. --Txuspe (talk) 11:01, 30 March 2020 (UTC)

Claims of "DEPRECATED" status

The tz database documentation never states that zones are deprecated. Many or all of the zones so listed here are in the backward file, which is a list of older zone names that officially remain supported. See the theory documentation for further discussion. — Preceding unsigned comment added by 74.96.142.96 (talk) 19:46, 15 April 2020 (UTC)

I think it is helpful to distinguish zones in the backward file from other zones, but I think it should be done consistently. It isn't. For example, Asia/Macao has been in the backward file since at least 2006, but has status 'alias', whereas Australia/ACT has status 'deprecated'. Neither appears in any other file. There are several other examples like this. Ookisan (talk) 14:27, 13 July 2020 (UTC)

Upate to 2020a?

Would anyone object to the page being updated to 2020a? Would anyone object to all timezones in the backward file being listed as 'deprecated' (see the 'Claims of "DEPRECATED" status' topic above for why)? The page doesn't match 2017c as it is since several edits have already been made to individual timezones. Ookisan (talk) 14:36, 13 July 2020 (UTC)

Synced to 2020d and beyond

I just did a large sync of the entire page with data I took from a 2020-10-30 snapshot of the GitHub repo. The snapshot is almost the same as 2020d.

• I took the liberty of marking most of the entries from the backward file as deprecated because several people appear to have asked for that.
• I preserved wiki links and comments in column #8 except where there were "Link to..." entries that were linked to the wrong zone.
• I preserved the wiki links in column #3 as best I could but I did not validate them.
• Everything in column #4 I threw away and replaced with the real comments from either zone1970.tab or zone.tab. I favored zone1970.tab which means we now have some UTF-8 characters in column #4.
• Some people may be upset that I overwrote column #4, but it is supposed to show exactly what is in the database so I am not feeling too guilty.
• I honored the "isdst" bit, thus the offset times for Dublin are the reverse of what the table previously showed.
• Ahh... yes, I also snuck the Factory zone into the table because otherwise it did not feel complete.
• The summary table at the bottom of the page is now up to date.
• That's it; that's all.

MapGrid (talk) 01:58, 31 October 2020 (UTC)

Deprecated

I mentioned that I marked most zones from the backward file as Deprecated. Was that the correct thing to do? I am now looking at Ookisan's comment in the talk page archives. I could do something like this:

1. In the status column show only Canonical or Alias. All backward entries would show up as aliases because that is what they really are.
2. Create a new column that shows the source file (northamerica, factory, backward, europe, etcetera, etc.)
3. Remove column #1 because coordinates are not very useful.

MapGrid (talk) 02:35, 31 October 2020 (UTC)

Time zone abbreviations

I realize the table is wide already, but I would like to try adding two narrow columns:

1. time zone abbreviation for standard time (e.g. EST)
2. time zone abbreviation for daylight saving time (e.g. EDT)

Does anybody have strong opinions? MapGrid (talk) 02:47, 31 October 2020 (UTC)

Note that not all TZDB regions have those abbreviations; some regions have even had the abbreviations removed from the TZDB and replaced by "+{offset}"-style values, in cases where one was invented, in the past, when there wasn't already a well-established English-language abbreviation. Guy Harris (talk) 10:02, 25 December 2020 (UTC)

ISO 3166-1 or 3166-2 country codes?

Is there some reason to use ISO 3166-2 country codes? TZDB regions don't necessarily correspond to subdivisions of the sort that are assigned ISO 3166-2 codes; for example, in the United States, most TZDB regions cover multiple subdivisions given in ISO 3166-2:US, and there are some such subdivisions that where different parts of the subdivision are in different TZDB regions. Guy Harris (talk) 10:06, 25 December 2020 (UTC)

After giving it some thought, I do not think there is any valid reason to use ISO 3166-2 codes. Somebody at some point in the past started changing the links from 3166-1 to 3166-2; they got as far as the first nine zones in the list and then stopped. I wanted to see some consistency so I applied the change to all zones, but that was probably a poor choice on my part. I am going to switch everything to 3166-1. MapGrid (talk) 14:17, 25 December 2020 (UTC)

Done. They are all 3166-1 now. MapGrid (talk) 14:29, 25 December 2020 (UTC)

Thanks. I didn't know whether there was a reason that I was missing, or not. (Perhaps whoever changed them thought that there is always a straightforward correspondence between TZDB regions and country subdivisions.) Guy Harris (talk) 21:46, 25 December 2020 (UTC)