Re: Proposal: Conflict log history table for Logical Replication

On Tue, Nov 25, 2025 at 4:06 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Tue, Nov 25, 2025 at 1:59 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
> >
>
> On a separate note, I've been considering how to manage conflict log
> insertions when an error causes the outer transaction to abort, which
> seems to be a non-trivial.
>
> Here is what I have in mind:
> ======================
> First, prepare_conflict_log() would be executed from
> ReportApplyConflict(). This function would handle all preliminary
> work, such as preparing the tuple for the conflict log table. Second,
> insert_conflict_log() would be executed. If the error level in
> ReportApplyConflict() is LOG, the insertion would occur directly.
> Otherwise, the log information would be stored in a global variable
> and inserted in a separate transaction once we exit start_apply() due
> to the error.
>
> @shveta malik @Amit Kapila let me know what you think?  Or do you
> think it can be simplified?
>

I could not think of a better way. This idea works for me. I had
doubts if it will be okay to start a new transaction in catch-block
(if we plan to do it in start_apply's), but then I found few other
functions doing it (see do_autovacuum, perform_work_item,
_SPI_commit). So IMO, we should be good.

thanks
Shveta