Re: pg_walfile_name_offset can return inconsistent values

On Fri, Nov 10, 2023 at 08:25:35AM +0900, Michael Paquier wrote:
> On Thu, Nov 09, 2023 at 04:14:07PM -0500, Bruce Momjian wrote:
> > Attached is the full patch that changes pg_walfile_name_offset() and
> > pg_walfile_name(). There is no need for doc changes. We need to
> > document this as incompatible in case users are realying on the old
> > behavior for WAL archiving purposes. If they want the old behavior they
> > need to check for an offset of zero and subtract one from the file name.
>
> FWIW, I am not really convinced that there is a strong need to
> backpatch any of that. There's a risk that some queries relying on
> the old behavior suddenly break after a minor release, and that's
> always annoying. A HEAD-only change seems like a safer bet to me.

Yes, this cannot be backpatched, clearly.

> > Can someone check that all other calls to XLByteToPrevSeg() are correct?
>
> On a quick check, all the other calls use that for end record LSNs, so
> that looks fine.

Thank you.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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