Re: Column Filtering in Logical Replication

On 3/17/22 15:17, Peter Eisentraut wrote:
> I notice that the publication.sql regression tests contain a number of
> comments like
>
> +-- error: replica identity "a" not included in the column list
> +ALTER PUBLICATION testpub_fortable ADD TABLE testpub_tbl5 (b, c);
>
> but the error doesn't actually happen, because of the way the replica
> identity checking was changed.  This needs to be checked again.

But the comment describes the error for the whole block, which looks
like this:

-- error: replica identity "a" not included in the column list
ALTER PUBLICATION testpub_fortable ADD TABLE testpub_tbl5 (b, c);
UPDATE testpub_tbl5 SET a = 1;
ERROR: cannot update table "testpub_tbl5"
DETAIL: Column list used by the publication does not cover the replica
identity.

So IMHO the comment is correct.

But there was one place where it wasn't entirely clear, as the block was
split by another comment. So I tweaked it to:

-- error: change the replica identity to "b", and column list to (a, c)
-- then update fails, because (a, c) does not cover replica identity

Attached is a rebased patch, on top of the two fixes I pushed.

regards

--
Tomas Vondra
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