From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Celia McInnis <celia.mcinnis@gmail.com>,
        "pgsql-generallists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: Re: altering a column to to make it generated
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Mon, 22 Apr 2024 12:45:46 -0700"
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Date: Mon, 22 Apr 2024 16:11:43 -0400
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Mon, Apr 22, 2024 at 12:42 PM Celia McInnis <celia.mcinnis@gmail.com>
> wrote:
>> Can I alter a table column to now make it generated? I tried this
>> unsuccessfully:

> I looked at all of the "alter table ... alter column" commands listed here:
> https://www.postgresql.org/docs/current/sql-altertable.html
> And none seem to involve the generated expression column.  So the answer is
> no.

I think what you'd need to do is drop the existing column
and then add a generated column.

			regards, tom lane