Re: Should AT TIME ZONE be volatile?

>Laurenz Albe <laurenz.albe@cybertec.at> writes:
>> On Thu, 2021-11-11 at 09:52 -0500, Tom Lane wrote:
>>> Yup.  If we had reliable ways to detect changes in this sort of
>>> environment-supplied data, maybe we could do something about it
>>> (a la the work that's been happening on attaching collation versions
>>> to indexes).  But personally I can't summon the motivation to work
>>> on that, when ICU is the *only* such infrastructure that offers
>>> readily program-readable versioning.

>> Nobody will want to hear that, but the only really good solution would
>> be for PostgreSQL to have its own built-in collations.

>And our own tzdb too?  Maybe an outfit like Oracle has the resources
>and will to maintain their own copies of such data, but I can't see
>us wanting to do it.

>tzdb has an additional problem, which is that not updating is not an
>option: if you're affected by a DST law change, you want that update,
>and you frequently need it yesterday.  We're definitely not set up
>to handle that sort of update process, which is why we recommend
>--with-system-tzdata.

Where in the docs is this recommended? The only place I can find it is here:
https://www.postgresql.org/docs/current/install-procedure.html

Regards
Daniel