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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Karsten Hilbert <Karsten.Hilbert@gmx.net>
cc: pgsql-general@lists.postgresql.org,
        pgsql-general <pgsql-general@postgresql.org>
Subject: Re: unique constraint violation on multiple-rows update
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Comments: In-reply-to Karsten Hilbert <Karsten.Hilbert@gmx.net>
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Karsten Hilbert <Karsten.Hilbert@gmx.net> writes:
> Am Sun, Apr 19, 2026 at 06:54:02AM -0700 schrieb David G. Johnston:
>> You know about deferred constraints, you should use them here.  This is one
>> of the key use cases motivating their existence.

> Indeed. I was of the mistaken impression that UNIQUE
> constraints were not deferrable ...

Once upon a time they were not, but we fixed that years ago.

			regards, tom lane