RE: Selectively invalidate caches in pgoutput module - Mailing list pgsql-hackers

On Monday, March 10, 2025 7:00 PM Kuroda, Hayato <kuroda.hayato@fujitsu.com> wrote:
> 
> I did a self-reviewing and updated a patch. PSA new version. What's new:

Thanks for updating the patch.

I tested the behavior for partitioned table and have a comment on this.

> +        relids = GetPublicationRelations(pubform->oid,
> +                                         PUBLICATION_PART_LEAF);

Currently, only the leaf partition is invalidated when the published table is
partitioned. However, I think pgoutput could cache both the partitioned table
and the leaf partition table as relsync entries.

For INSERT/UPDATE/DELETE on a partitioned table, only the leaf partition's
relsync entry is used in pgoutput, but the TRUNCATE references the parent
table's relsync entry.

For example[1], if the parent table's relsync entry is not invalidated after a
RENAME operation, it results in the TRUNCATE to be missed. So I think we should
Invalidate all the tables in the partition tree by passing
PUBLICATION_PART_ALL, which is also consistent with ALTER PUB ADD/SET/DROP
TABLE.


[1]--- Example ---
create table test(a int primary key) PARTITION BY RANGE (a);
CREATE TABLE test_1 PARTITION OF test
    FOR VALUES FROM (0) TO (2);
CREATE TABLE test_2 PARTITION OF test
    FOR VALUES FROM (2) TO (4);

CREATE PUBLICATION pub;
CREATE PUBLICATION pub2 FOR TABLE test WITH (PUBLISH_VIA_PARTITION_ROOT);

SELECT 'init' FROM pg_create_logical_replication_slot('isolation_slot', 'pgoutput');

TRUNCATE test;
ALTER PUBLICATION pub RENAME TO pub3;
ALTER PUBLICATION pub2 RENAME TO pub;
TRUNCATE test;

-- I can consume some changes using the following function on HEAD, but got
-- nothing after applying the patch.
SELECT * FROM pg_logical_slot_get_binary_changes('isolation_slot', NULL, NULL, 'proto_version', '4',
'publication_names','pub', 'streaming', 'on');
 

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Best Regards,
Hou zj