Message-ID: <258b6521-100e-48da-a7c4-b069ba3df007@163.com>
Date: Tue, 21 Apr 2026 15:03:39 +0800
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Subject: Re: repack: fix a bug to reject deferrable primary key fallback for
 concurrent mode
To: Antonin Houska <ah@cybertec.at>, Chao Li <li.evan.chao@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>,
 "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>,
 Alvaro Herrera <alvherre@alvh.no-ip.org>
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 <5990.1776751782@localhost>
From: Yuchen Li <liyuchen_xyz@163.com>
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On 4/21/2026 2:09 PM, Antonin Houska wrote:
> Chao Li <li.evan.chao@gmail.com> wrote:
>
>>> On Apr 20, 2026, at 22:52, Antonin Houska <ah@cybertec.at> wrote:
>>>
>>> I'm just thinking if it's worth a separate error message.
>>> RelationGetIndexList() just ignores the deferrable PK
>>>
>>> if (replident == REPLICA_IDENTITY_DEFAULT && OidIsValid(pkeyIndex) && !pkdeferrable)
>>> relation->rd_replidindex = pkeyIndex;
>>>
>>> and if there's no other suitable index, the result is that there is no
>>> identity index for the table. So the change attached here should be consistent
>>> with this approach.
>> Thanks for your review. I guess you read the v1 patch. In v2, I have switched to use GetRelationIdentityOrPK() that Zhijie suggested, which has covered RelationGetIndexList() and all checks, so that code is simplified, and there is no longer a separate error message.
> Yes, this looks like the best approach. Sorry for missing v2.
>
The patch looks good to me. Using GetRelationIdentityOrPK() makes the 
check match the intended replica identity semantics more closely, and 
the added regression coverage looks useful.

Regards,
Yuchen Li