From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Ron <ronljohnsonjr@gmail.com>,
        "pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>
Subject: Re: Reordering the fields in a table
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Sat, 17 Apr 2021 08:21:34 -0700"
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Date: Sat, 17 Apr 2021 11:40:30 -0400
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> The feature has been discussed before on these lists and the only thing
> preventing its inclusion is some developers either donating their time to
> see it finished or some interested non-developers paying some developers to
> write it on their behalf.

It's not just whether somebody finishes a patch.  The real concern
here is that separating logical from physical column order would
inevitably cause great quantities of bugs, probably including some
on the client side.  If our experience with dropped columns is any
guide, it'd probably take *years* to flush out all the places that
misbehave when dealing with re-ordered columns.  So maybe it'll
happen eventually, but it'll be far from pain-free.

(FWIW, I recall that Alvaro Herrera had a semi-finished patch
in this area a few years ago.  If anyone is interested in
pursuing this, starting from that would likely be useful.)

			regards, tom lane