On Tue, Jun 16, 2026 at 6:52 AM Peter Smith <[email protected]> wrote:
>
> This discussion about the impact of ALTER TABLE ... SET SCHEMA made me
> wonder what happens for the existing PG19 case of FOR ALL TABLES
> EXCEPT (TABLE ...)
>
> It turns out to be quite different:
>
> ======
>
> test_pub=# CREATE SCHEMA myschema;
> CREATE SCHEMA
> test_pub=# CREATE TABLE t1(A INT);
> CREATE TABLE
> test_pub=# CREATE TABLE t2(A INT);
> CREATE TABLE
> test_pub=# CREATE TABLE myschema.myt1(A INT);
> CREATE TABLE
> test_pub=# CREATE PUBLICATION pub1 FOR ALL TABLES EXCEPT (TABLE 
> myschema.myt1);
> CREATE PUBLICATION
> test_pub=# \d myschema.myt1
>                Table "myschema.myt1"
>  Column |  Type   | Collation | Nullable | Default
> --------+---------+-----------+----------+---------
>  a      | integer |           |          |
> Excluded from publications:
>     "pub1"
>
> test_pub=# \dRp+ pub1
>                                                        Publication pub1
>   Owner   | All tables | All sequences | Inserts | Updates | Deletes |
> Truncates | Generated columns | Via root | Descri
> ption
> ----------+------------+---------------+---------+---------+---------+-----------+-------------------+----------+-------
> ------
>  postgres | t          | f             | t       | t       | t       |
> t         | none              | f        |
> Except tables:
>     "myschema.myt1"
>
> test_pub=# ALTER TABLE myschema.myt1 SET SCHEMA public;
> ALTER TABLE
> test_pub=# \d myt1
>                 Table "public.myt1"
>  Column |  Type   | Collation | Nullable | Default
> --------+---------+-----------+----------+---------
>  a      | integer |           |          |
> Excluded from publications:
>     "pub1"
>
> test_pub=# \dRp+ pub1
>                                                        Publication pub1
>   Owner   | All tables | All sequences | Inserts | Updates | Deletes |
> Truncates | Generated columns | Via root | Descri
> ption
> ----------+------------+---------------+---------+---------+---------+-----------+-------------------+----------+-------
> ------
>  postgres | t          | f             | t       | t       | t       |
> t         | none              | f        |
> Except tables:
>     "public.myt1"
>
> ======
>
> This experiment shows that moving the table did *not* remove the exclusion.
>
> It is kind of "explainable" in hindsight because the exclusion is by
> table OID, not name, so it follows the table around when it is moved.
> I don't think this is what a user would expect, given that they
> explicitly asked to exclude it from a different schema.
>
> Is it a PG19 exclusion bug?
>
> Is it behaviour that needs more documenting?
>
> ~
>
> IMO it seemed like a bug of the PG19 FOR ALL TABLES EXCEPT, because it
> is the opposite of what the new FOR TABLES IN SCHEMA EXCEPT patch
> does:
> "If a table listed in the <literal>EXCEPT</literal> clause is later
> moved to a different schema using  <command>ALTER TABLE ... SET
> SCHEMA</command>, the exclusion is removed;"
>

No, I don't think this is a bug for PG19 and the new behaviour for
PG20 is intentional and required because in this case, the EXCEPT
clause is schema-scoped, so once schema is changed, the table should
be removed from the exclusion list. OTOH, in PG19, the exclusion list
follows the table-level exclusion based on its OID as we can see in
the example provided by you. I think we can consider adding a line for
this in docs if you and others feel that such explicit mention can
avoid ambiguity around this. How about something like the following as
a separate para in EXCEPT clause description: Once a table is
excluded, the exclusion applies to that table itself, regardless of
its name or schema. Renaming the table or moving it to another schema
with <command>ALTER TABLE ... SET SCHEMA</command> does not cancel the
exclusion."

-- 
With Regards,
Amit Kapila.


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