From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
cc: Arne Roland <A.Roland@index.de>, vignesh C <vignesh21@gmail.com>,
        Zhihong Yu <zyu@yugabyte.com>,
        Pg Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Rename of triggers for partitioned tables
In-reply-to: <202107222235.djjcscrqxpwn@alvherre.pgsql>
References: <202107222235.djjcscrqxpwn@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@alvh.no-ip.org>
	message dated "Thu, 22 Jul 2021 18:35:25 -0400"
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Date: Sun, 25 Jul 2021 10:49:43 -0400
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Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> I pushed this patch with some minor corrections (mostly improved the
> message wording.)

Coverity does not like this bit, and I fully agree:

/srv/coverity/git/pgsql-git/postgresql/src/backend/commands/trigger.c: 163=
9 in renametrig_partition()
>>>     CID 1489387:  Incorrect expression  (ASSERT_SIDE_EFFECT)
>>>     Argument "found++" of Assert() has a side effect.  The containing =
function might work differently in a non-debug build.
1639     		Assert(found++ <=3D 0);

Perhaps there's no actual bug there, but it's still horrible coding.
For one thing, the implication that found could be negative is extremely
confusing to readers.  A boolean might be better.  However, I wonder why
you bothered with a flag in the first place.  The usual convention if
we know there can be only one match is to just not write a loop at all,
with a suitable comment, like this pre-existing example elsewhere in
trigger.c:

		/* There should be at most one matching tuple */
		if (HeapTupleIsValid(tuple =3D systable_getnext(tgscan)))

If you're not quite convinced there can be only one match, then it
still shouldn't be an Assert --- a real test-and-elog would be better.

			regards, tom lane