Re: mark the timestamptz variant of date_bin() as stable - Mailing list pgsql-hackers

From Tom Lane
Subject Re: mark the timestamptz variant of date_bin() as stable
Date
Msg-id 2117318.1630524355@sss.pgh.pa.us
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In response to Re: mark the timestamptz variant of date_bin() as stable  (John Naylor <john.naylor@enterprisedb.com>)
Responses Re: mark the timestamptz variant of date_bin() as stable
Re: mark the timestamptz variant of date_bin() as stable
List pgsql-hackers
John Naylor <john.naylor@enterprisedb.com> writes:
> On Wed, Sep 1, 2021 at 2:44 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I see that these two answers are both exactly multiples of 24 hours away
>> from the given origin.  But if I'm binning on the basis of "days" or
>> larger units, I would sort of expect to get local midnight, and I'm not
>> getting that once I cross a DST boundary.

> Hmm, that's seems like a reasonable expectation. I can get local midnight
> if I recast to timestamp:

> # select date_bin('1 day', '2021-11-10 00:00 +00'::timestamptz::timestamp,
> '2021-09-01 00:00 -04'::timestamptz::timestamp);
>       date_bin
> ---------------------
>  2021-11-09 00:00:00
> (1 row)

Yeah, and then back to timestamptz if that's what you really need :-(

> It's a bit unintuitive, though.

Agreed.  If we keep it like this, adding some documentation around
the point would be a good idea I think.

            regards, tom lane



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