Re: date_trunc function in interval version

Hi,

Please don't too-post on this list. The custom is to bottom-post or
reply inline, and it's much easier to follow such replies.

On 12/23/23 23:45, Przemysław Sztoch wrote:
> date_bin has big problem with DST.
> In example, if you put origin in winter zone, then generated bin will be
> incorrect for summer input date.
>
> date_trunc is resistant for this problem.
> My version of date_trunc is additionally more flexible, you can select
> more granular interval, 12h, 8h, 6h, 15min, 10 min etc...
>

I'm not very familiar with date_bin(), but is this issue inherent or
could we maybe fix date_bin() to handle DST better?

In particular, isn't part of the problem that date_bin() is defined only
for timestamp and not for timestamptz? Also, date_trunc() allows to
specify a timezone, but date_bin() does not.

In any case, the patch needs to add the new stuff to the SGML docs (to
doc/src/sgml/func.sgml), which now documents the date_trunc(text,...)
variant only.

regards

--
Tomas Vondra
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