Feedback-ID: id4a34324:Fastmail
Date: Mon, 9 Mar 2026 10:01:53 -0400
From: Andres Freund <andres@anarazel.de>
To: Greg Sabino Mullane <htamfids@gmail.com>
Cc: Tomas Vondra <tomas@vondra.me>,
	Alexandre Felipe <o.alexandre.felipe@gmail.com>,
 Ayush Tiwari <ayushtiwari.slg01@gmail.com>,
	pgsql-hackers@postgresql.org
Subject: Re: tid_blockno() and tid_offset() accessor functions
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Hi,

On 2026-03-09 09:34:46 -0400, Greg Sabino Mullane wrote:
> On Sun, Mar 8, 2026 at 3:31 PM Tomas Vondra <tomas@vondra.me> wrote:
> 
> > No opinion. For displaying the bogus TID value (like "(-1,0)") it's
> > probably OK to show values that are a bit weird. If anything, we should
> > be more careful on input, it's too late for tid_block() to decide what to
> > do with an "impossible" TID value.
> >
> 
> This one doesn't sit right with me. I think it's not too late. No reason
> why tid_block cannot be stricter here than tid itself and complain. Other
> than that, the patch looks good to me.

I don't see any advantage in that. These functions are useful for inspecting
tid values that come from some source. When would you *ever* gain *anything*
from not being able to see the block / offset of a tid datum that you already
have?

This isn't an end user focused type / set of accessor functions were being
particularly careful about input validation will perhaps prevent users from
making mistakes...

Greetings,

Andres Freund