Re: [PATCH] Improve REPACK (CONCURRENTLY) error messages for unsupported configurations

On 2026-May-27, Chao Li wrote:

> > 0002 -- check_concurrent_repack_requirements() reports the same
> > generic "no identity index" error for several distinct
> > cases, two of which are misleading: REPLICA IDENTITY FULL
> > (which is set, but the hint says there is no identity), and
> > a deferrable PK as the only identity (skipped per commit
> > 832e220d99a, but the hint suggests adding an index that
> > already exists). Distinguish these cases.
>
> When I was working on 832e220d99a, I actually considered for more
> detailed error messages, but I ended up giving up. I think we should
> be careful about adding more branches here unless the existing message
> is causing significant confusion in practice.

I pushed this one too (well, something close to it anyway), because I
think the replica identity issue could be an (unnecessary) usability
tripwire.

I'm curious to know why you gave up on this, if you want to share more.

Thanks both,

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
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