Re: why can't a table be part of the same publication as its schema

On 14.09.22 07:10, houzj.fnst@fujitsu.com wrote:
> After applying the patch, we support adding a table with column list along with
> the table's schema[1], and it will directly apply the column list in the
> logical replication after applying the patch.
> 
> [1]--
> CREATE PUBLICATION pub FOR TABLE public.test(a), FOR ALL TABLES IN SCHEMA public;
> -----
> 
> If from the point of view of consistency, for column list, we could report an
> ERROR because we currently don't allow using different column lists for a
> table. Maybe an ERROR like:
> 
> "ERROR: cannot use column for table x when the table's schema is also in the publication"
> 
> But if we want to report an ERROR for column list in above case. We might need
> to restrict the ALTER TABLE SET SCHEMA as well because user could move a table
> which is published with column list to a schema that is also published in the
> publication, so we might need to add some similar check(which is removed in
> Vignesh's patch) to tablecmd.c to disallow this case.
> 
> Another option could be just ingore the column list if table's schema is also
> part of publication. But it seems slightly inconsistent with the rule that we
> disallow using different column list for a table.

Ignoring things doesn't seem like a good idea.

A solution might be to disallow adding any schemas to a publication if 
column lists on a table are specified.