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From: "David G. Johnston" <david.g.johnston@gmail.com>
Date: Tue, 5 May 2026 16:27:42 -0700
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 <CAKFQuwYWhSxoCPf9RTVVgs96oU78rdh3Aj05s2PCppb1GscA8g@mail.gmail.com>
Subject: Re: Suspected documentation error
To: scoobster17@gmail.com, pgsql-docs@lists.postgresql.org
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On Tue, May 5, 2026 at 3:02=E2=80=AFPM PG Doc comments form <noreply@postgr=
esql.org>
wrote:

> As such, whilst looking through this page
> (https://www.postgresql.org/docs/current/functions-formatting.html) as
> shown
> in the Udemy course I'm following, I noticed that the notes "OF" state
> "time-zone offset from UTC (HH or HH:MM)", which I believe should be
> "time-zone offset from UTC (HH or HH:MI)".
>
>
Technically interpreting either of those according to the format specifiers
co-located in that table is wrong.  All HH and MM stand for here are hours
and minutes, trying to communicate fixed two-digits.

psql -c "SET LOCAL timezone =3D 'Pacific/Apia'; SELECT to_char(now(),
'YYYY-MM-DD HH24:MI:SS OF') AS plus13_apia;"

       plus13_apia
-------------------------
 2026-05-06 12:11:49 +13
(1 row)

HH is defined on the range 0-12 but here we see we get +13 (and it's easy
to also produce negative offsets).

That said, the way I'd fix this is:

TZH - time-zone hours offset from UTC , signed, two-digits, e.g., -04 or +0=
5
TZM - time-zone minutes offset from UTC, unsigned two-digit (to append, not
add), e.g., 00 or 30
OF - TZH[:TZM] time-zone offset, but minutes are suppressed when zero.
e.g., -04 or +05:30

David J.

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<div dir=3D"ltr"><div dir=3D"ltr"><div class=3D"gmail_default" style=3D"fon=
t-family:arial,helvetica,sans-serif"><span style=3D"font-family:Arial,Helve=
tica,sans-serif">On Tue, May 5, 2026 at 3:02=E2=80=AFPM PG Doc comments for=
m &lt;<a href=3D"mailto:noreply@postgresql.org">noreply@postgresql.org</a>&=
gt; wrote:</span></div></div><div class=3D"gmail_quote gmail_quote_containe=
r"><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;bord=
er-left:1px solid rgb(204,204,204);padding-left:1ex">As such, whilst lookin=
g through this page<br>
(<a href=3D"https://www.postgresql.org/docs/current/functions-formatting.ht=
ml" rel=3D"noreferrer" target=3D"_blank">https://www.postgresql.org/docs/cu=
rrent/functions-formatting.html</a>) as shown<br>
in the Udemy course I&#39;m following, I noticed that the notes &quot;OF&qu=
ot; state<br>
&quot;time-zone offset from UTC (HH or HH:MM)&quot;, which I believe should=
 be<br>
&quot;time-zone offset from UTC (HH or HH:MI)&quot;.<br><br></blockquote><d=
iv><br></div><div class=3D"gmail_default" style=3D"font-family:arial,helvet=
ica,sans-serif">Technically interpreting either of those according to the f=
ormat specifiers co-located in that table is wrong.=C2=A0 All HH and MM sta=
nd for here are hours and minutes,=C2=A0trying to communicate fixed two-dig=
its.</div><div class=3D"gmail_default" style=3D"font-family:arial,helvetica=
,sans-serif"><br></div><div class=3D"gmail_default" style=3D"font-family:ar=
ial,helvetica,sans-serif">psql -c &quot;SET LOCAL timezone =3D &#39;Pacific=
/Apia&#39;; SELECT to_char(now(), &#39;YYYY-MM-DD HH24:MI:SS OF&#39;) AS pl=
us13_apia;&quot;</div><div class=3D"gmail_default" style=3D"font-family:ari=
al,helvetica,sans-serif"><br></div><div class=3D"gmail_default" style=3D"fo=
nt-family:arial,helvetica,sans-serif">=C2=A0 =C2=A0 =C2=A0 =C2=A0plus13_api=
a =C2=A0 =C2=A0 =C2=A0 <br>-------------------------<br>=C2=A02026-05-06 12=
:11:49 +13<br>(1 row)<br><br>HH is defined on the range 0-12 but here we se=
e we get=C2=A0+13 (and it&#39;s easy to also produce negative offsets).</di=
v><div class=3D"gmail_default" style=3D"font-family:arial,helvetica,sans-se=
rif"><br></div><div class=3D"gmail_default" style=3D"font-family:arial,helv=
etica,sans-serif">That said, the way I&#39;d fix this is:</div><div class=
=3D"gmail_default" style=3D"font-family:arial,helvetica,sans-serif"><br></d=
iv><div class=3D"gmail_default" style=3D"font-family:arial,helvetica,sans-s=
erif">TZH - time-zone hours offset from UTC , signed, two-digits, e.g., -04=
 or +05</div><div class=3D"gmail_default" style=3D"font-family:arial,helvet=
ica,sans-serif">TZM - time-zone minutes offset from UTC, unsigned two-digit=
 (to append, not add), e.g., 00 or 30</div><div class=3D"gmail_default" sty=
le=3D"font-family:arial,helvetica,sans-serif">OF - TZH[:TZM] time-zone offs=
et, but minutes are suppressed when zero. e.g., -04 or +05:30</div><div cla=
ss=3D"gmail_default" style=3D"font-family:arial,helvetica,sans-serif"><br><=
/div><div class=3D"gmail_default" style=3D"font-family:arial,helvetica,sans=
-serif">David J.</div><div class=3D"gmail_default" style=3D"font-family:ari=
al,helvetica,sans-serif"><br></div><div class=3D"gmail_default" style=3D"fo=
nt-family:arial,helvetica,sans-serif"></div></div></div>

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