From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bruce Momjian <bruce@momjian.us>
cc: Tim <timfosho@gmail.com>, Paul Smith <paul@pscs.co.uk>,
        pgsql-admin@lists.postgresql.org
Subject: Re: Creating redwood datestyle in Postgres 12
In-reply-to: <20210326123555.GA18244@momjian.us>
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Comments: In-reply-to Bruce Momjian <bruce@momjian.us>
	message dated "Fri, 26 Mar 2021 08:35:55 -0400"
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Date: Fri, 26 Mar 2021 09:42:28 -0400
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Bruce Momjian <bruce@momjian.us> writes:
> On Fri, Mar 26, 2021 at 08:24:37AM -0400, Tim wrote:
>> I suppose that would be possible, but maintaining=C2=A0date triggers + =
views across
>> a large database would be a lot of work. I'm just one humble DBA and th=
ere is
>> 15-20 devs

> You probably need a custom data type with a custom C output function do
> to this efficiently.

If you're willing to write C code it likely wouldn't be that hard
to modify datetime output to honor a new datestyle value.  (Input
is messier, but since we already read this format okay, I don't
think anything is needed on that end.)

It would seem reasonable to me to have a datestyle that emits
the month as a 3-letter abbreviation, so that you could get
'2021-Mar-26' or '26-Mar-2021' etc depending on the YMD/DMY/MDY
setting.  I'd draw the line at emitting 2-digit years though.
(If you need to be that bug-compatible with Oracle, you should
stick with EDB --- that's what their AS product is for.)

			regards, tom lane