Date: Mon, 20 Oct 2025 13:05:38 +0200
From: "Peter J. Holzer" <hjp-pgsql@hjp.at>
To: pgsql-general@lists.postgresql.org
Subject: Re: Convert date and time colums to datetime
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Subject: Re: Convert date and time colums to datetime
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On 2025-10-19 20:32:07 -0600, Rob Sargent wrote:
> > On Oct 19, 2025, at 2:38=E2=80=AFPM, Rich Shepard <rshepard@appl-ecosys=
=2Ecom> wrote:
> > On Sun, 19 Oct 2025, Rob Sargent wrote:
> >> I think you have to ask why those values were separated in the first
> >> place. For instance if they are thought of as a pair in most queries t=
hen
> >> an alteration might be in order. There can be a large one time cost if
> >> these tables occur in a lot of separate sql calls in the business logi=
c.
> >=20
> > Good point. They're in the contacts table and I use them to determine w=
hen
> > to make another contact and if prior contacts were more productive in t=
he
> > morning or afternoon.
>=20
> Definitely a datetime (single value) problem, imho

Actually, to me that seems to be one of the few cases where splitting
them makes sense. I would expect typical updates to be something like
"sane time, but 6 months later" or "same day, but different time". There
might also be constraints like "not before 9am". For queries there might
be stuff like "who do I need to call today", or as Rich already
mentioned, statistics by time of the day. There are probably relatively
few queries where you need to treat date and time as a unit.

        hjp

--=20
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp@hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"

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