Re: Disallow UPDATE/DELETE on table with unpublished generated column as REPLICA IDENTITY

On 2024-Nov-07, Amit Kapila wrote:

> BTW, I was thinking as to how to fix it on back branches and it seems
> we should restrict to define REPLICA IDENTITY on stored generated
> columns in the first place in back branches as those can't be
> replicated. So, the following should fail:
>
> CREATE TABLE testpub_gencol (a INT, b INT GENERATED ALWAYS AS (a + 1)
> STORED NOT NULL);
> CREATE UNIQUE INDEX testpub_gencol_idx ON testpub_gencol (b);
> ALTER TABLE testpub_gencol REPLICA IDENTITY USING index testpub_gencol_idx;
>
> Peter, do you have an opinion on this?

I think a blanket restriction of this sort is not a good idea (at least
in back branches), because there might be people using replica
identities with stacks other than pgoutput. Would it work to enforce
the restriction when such a table is added to a publication?

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