Re: tid_blockno() and tid_offset() accessor functions

Hi,

Thank you all for the reviews and discussion!

On the strictness question raised by Greg — I agree with Andres here. These
functions are meant for inspecting tid values that already exist, so
rejecting "impossible" values like (-1,0) would not be providing any real
benefit. I believe the tid input function is the appropriate place for any
validation, and these assessors should just faithfully report what's in the
datum.

Regards,
Ayush

On Mon, 9 Mar 2026 at 19:32, Andres Freund <andres(at)anarazel(dot)de> wrote:

> 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(at)vondra(dot)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
>