Re: pg_waldump and PREPARE

On Fri, Apr 26, 2019 at 5:38 AM Michael Paquier <michael(at)paquier(dot)xyz> wrote:
>
> On Thu, Apr 25, 2019 at 03:08:36PM -0400, Alvaro Herrera wrote:
> > On 2019-Apr-26, Fujii Masao wrote:
> >> I did that arrangement because the format of PREPARE TRANSACTION record,
> >> i.e., that struct, also needs to be accessed in backend and frontend.
> >> But, of course, if there is smarter way, I'm happy to adopt that!
> >
> > I don't know. I spent some time staring at the code involved, and it
> > seems it'd be possible to improve just a little bit on cleanliness
> > grounds, with a lot of effort, but not enough practical value.
>
> Describing those records is something we should do. There are other
> parsing routines in xactdesc.c for commit and abort records, so having
> that extra routine for prepare at the same place does not sound
> strange to me.
>
> +typedef xl_xact_prepare TwoPhaseFileHeader;
> I find this mapping implementation a bit lazy, and your
> newly-introduced xl_xact_prepare does not count for all the contents
> of the actual WAL record for PREPARE TRANSACTION. Wouldn't it be
> better to put all the contents of the record in the same structure,
> and not only the 2PC header information?

This patch doesn't apply anymore, could you send a rebase?