Re: Support logical replication of DDLs

On Fri, May 6, 2022 at 10:21 PM Zheng Li <zhengli10(at)gmail(dot)com> wrote:
>
> > Attached is a set of two patches as an attempt to evaluate this approach.
> >
>
> Thanks for exploring this direction.
>
> I read the deparsing thread and your patch. Here is my thought:
> 1. The main concern on maintainability of the deparsing code still
> applies if we want to adapt it for DDL replication.
>

I agree that it adds to our maintainability effort, like every time we
enhance any DDL or add a new DDL that needs to be replicated, we
probably need to change the deparsing code. But OTOH this approach
seems to provide better flexibility. So, in the long run, maybe the
effort is worthwhile. I am not completely sure at this stage which
approach is better but I thought it is worth evaluating this approach
as Alvaro and Robert seem to prefer this idea.

> 2. The search_path and role still need to be handled, in the deparsing
> code. And I think it's actually more overhead to qualify every object
> compared to just logging the search_path and enforcing it on the apply
> worker.
>

But doing it in the deparsing code will have the benefit that the
other plugins won't have to develop similar logic.

--
With Regards,
Amit Kapila.