Re: row filtering for logical replication

Peter Smith <smithpb2250@gmail.com>

From: Peter Smith <smithpb2250@gmail.com>
To: "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, vignesh C <vignesh21@gmail.com>, Greg Nancarrow <gregn4422@gmail.com>, "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>, Ajin Cherian <itsajin@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Euler Taveira <euler@eulerto.com>, Rahila Syed <rahilasyed90@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, Önder Kalacı <onderkalaci@gmail.com>, japin <japinli@hotmail.com>, Michael Paquier <michael@paquier.xyz>, David Steele <david@pgmasters.net>, Craig Ringer <craig@2ndquadrant.com>, Amit Langote <amitlangote09@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-11-29T02:08:21Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Release cache tuple when no longer needed

  2. Add some additional tests for row filters in logical replication.

  3. Fix one of the tests introduced in commit 52e4f0cd47.

  4. Allow specifying row filters for logical replication of tables.

  5. Move scanint8() to numutils.c

  6. Replace Test::More plans with done_testing

  7. Reduce relcache access in WAL sender streaming logical changes

  8. Small cleanups related to PUBLICATION framework code

  9. Add a view to show the stats of subscription workers.

  10. Allow publishing the tables of schema.

  11. Doc: improve documentation of CREATE/ALTER SUBSCRIPTION.

  12. Add PublicationTable and PublicationRelInfo structs

  13. Remove unused argument "txn" in maybe_send_schema().

  14. Add prepare API support for streaming transactions in logical replication.

  15. Unify PostgresNode's new() and get_new_node() methods

  16. Use l*_node() family of functions where appropriate

  17. Add support for prepared transactions to built-in logical replication.

  18. Restore the portal-level snapshot after procedure COMMIT/ROLLBACK.

  19. Rename a parse node to be more general

  20. Remove unused column atttypmod from initial tablesync query

  21. SEARCH and CYCLE clauses

On Sun, Nov 28, 2021 at 6:17 PM Peter Smith <smithpb2250@gmail.com> wrote:
>
> On Fri, Nov 26, 2021 at 1:16 PM houzj.fnst@fujitsu.com
> <houzj.fnst@fujitsu.com> wrote:
> >
> ...
> > Based on this direction, I tried to write a top up POC patch(0005) which I'd like to share.
> >
> > The top up patch mainly did the following things.
> >
> > * Move the row filter columns invalidation to CheckCmdReplicaIdentity, so that
> > the invalidation is executed only when actual UPDATE or DELETE executed on the
> > published relation. It's consistent with the existing check about replica
> > identity.
> >
> > * Cache the results of the validation for row filter columns in relcache to
> > reduce the cost of the validation. It's safe because every operation that
> > change the row filter and replica identity will invalidate the relcache.
> >
> > Also attach the v42 patch set to keep cfbot happy.
>

Now I looked at the patch 0005 test cases. Since this patch does the
RI validation at UPDATE/DELETE execution instead of at the time of
CREATE PUBLICATION it means that currently, the CREATE PUBLICATION is
always going to succeed. So IIUC I think it is accidentally missing a
DROP PUBLICATION for one of the tests because the "ERROR:  publication
"testpub6" already exists" should not be happening. Below is a
fragment from the regression test publication.out I am referring to:

CREATE PUBLICATION testpub6 FOR TABLE rf_tbl_abcd_pk WHERE (a > 99);
-- fail - "a" is in PK but it is not part of REPLICA IDENTITY NOTHING
UPDATE rf_tbl_abcd_pk set a = 1;
ERROR:  cannot update table "rf_tbl_abcd_pk"
DETAIL:  Not all row filter columns are not part of the REPLICA IDENTITY
CREATE PUBLICATION testpub6 FOR TABLE rf_tbl_abcd_pk WHERE (c > 99);
ERROR:  publication "testpub6" already exists

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Kind Regards,
Peter Smith.
Fujitsu Australia