Message-ID: <55bdb57fe6d84b0acb56c369c699546086b983ca.camel@cybertec.at>
Subject: Re: BUG #19393: pg_upgrade fails with duplicate key violation when
 CHECK constraint named *_not_null exists
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: =?ISO-8859-1?Q?=C1lvaro?= Herrera <alvherre@kurilemu.de>
Cc: huseyin.d3r@gmail.com, pgsql-bugs@lists.postgresql.org
Date: Sat, 21 Feb 2026 16:13:59 +0100
In-Reply-To: <202602211127.yhfjy43if2kk@alvherre.pgsql>
References: <202602211127.yhfjy43if2kk@alvherre.pgsql>
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On Sat, 2026-02-21 at 12:56 +0100, =C3=81lvaro Herrera wrote:
> > On Thu, 2026-02-05 at 15:58 +0100, I wrote:
> > > The bug is actually not in pg_upgrade, but in CREATE TABLE.  The atta=
ched patch
> > > fixes the problem for me by avoiding given constraint names when gene=
rating
> > > the names for NOT NULL constraints.
> >=20
> > ... and here is v2, including a regression test.
>=20
> Thanks for this!  I have pushed it now to 18 and master (right before
> the embargo for next week's release -- not really apologizing about
> that, since this is clearly something that's going to bite users as they
> move up to 18).

Thank you, and thanks for the code improvements.

> 1. this will cause an ABI break report for AddRelationNotNullConstraints
> in branch 18.  I considered the idea of adding a shim function
> preserving the original API, but I think this is not a function likely
> to be used by third-party code.  So I'll address this by adding an entry
> to .abi-compliance-history instead.

I decided not to worry about changing the signature of that global function=
,
because it is only used in a single place and - like you - I deem it unlike=
ly
to be useful elsewhere.

Yours,
Laurenz Albe