[tz] Adding Asia/Beijing timezone into the database

Eliot Lear lear at cisco.com
Thu Dec 8 08:03:18 UTC 2011

I believe this issue has been discussed repeatedly on this list, the
archives of which are available for your perusal.  My suggestion is that
until circumstances change that might impact the decision process, we
not revisit the whole argument.  If those circumstances have changed,
perhaps those proposing the change should indicate what they are.


On 12/8/11 8:44 AM, Daoming Qiu wrote:
> >From local custom and developer's preference, "Asia/Beijing" is natural choice.
> Beijing has almost same population as Shanghai, but there are very few
> people here to talk about Shanghai timezone.
> In windows or linux machine, you can only see "GMT+8  Beijing,
> Chongqing,HongKong,Urumuqi" in the timezone panel list,
> (there is no shanghai here).
> I am not an expert on time issues, and following is suggested zone
> info for Asia/Beijing:
> Zone	       Asia/Beijing	7:45:32	 -	        LMT	        1928
> 			                8:00	        PRC	        C%sT
> Thanks,
> Daoming
> On Wed, Dec 7, 2011 at 4:16 PM, Philip Newton <philip.newton at gmail.com> wrote:
>> On Wed, Dec 7, 2011 at 08:21, Daoming Qiu <qdaoming at gmail.com> wrote:
>>> "Beijing Time" is the standard time used for China region, so
>>>  it is very strange that tzdatabase doesn't have timezone called Asia/Beijing.
>> The database does not follow, in general, country lines but rather
>> regions that use the same timezone during the same period of time. And
>> because cities change their names less often than countries do, the
>> database usually uses city names (rather than country names) to
>> identify such timezone regions, and in general (in my understanding)
>> chooses the largest city within a timezone region to represent that
>> region. This favours Shanghai over Beijing.
>> You will note that there is also no America/Washington_DC, for
>> example, or Australia/Canberra, or America/Brasilia.
>> See also the "Theory" file in the tzcode distribution; this mentions
>> some of the things taken into account when choosing names of time
>> zones. (And it even has Shanghai/Beijing as an example: "Use the most
>> populous among locations in a country's time zone, e.g. prefer
>> `Shanghai' to `Beijing'.")
>>> Strongly suggest to add "Asia/Beijing" zone into the database,
>>> and its information is very similar with "Asia/Shanghai".
>> If it is only "similar", can you please provide information on when
>> Beijing used different time from Shanghai after January 1970? Then the
>> tz database can be corrected and completed.
>> Final disclaimer: I'm not a tz database maintainer and do not
>> represent anyone maintaining it or setting the rules. The above is my
>> understanding and interpretation.
>> Cheers,
>> Philip
>> --
>> Philip Newton <philip.newton at gmail.com>

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