Re: [HACKERS] Restrict concurrent update/delete with UPDATE of partition key

On Fri, Jan 26, 2018 at 1:28 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> So, this means that in case of logical replication, it won't generate
> the error this patch is trying to introduce. I think if we want to
> handle this we need some changes in WAL and logical decoding as well.
>
> Robert, others, what do you think? I am not very comfortable leaving
> this unaddressed, if we don't want to do anything about it, at least
> we should document it.

As I said on the other thread, I'm not sure how reasonable it really
is to try to do anything about this. For both the issue you raised
there, I think we'd need to introduce a new WAL record type that
represents a delete from one table and an insert to another that
should be considered as a single operation. I'm not keen on that idea,
but you can make an argument that it's the Right Thing To Do. I would
be more inclined, at least for v11, to just document that the
delete+insert will be replayed separately on replicas.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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