Re: row filtering for logical replication

Greg Nancarrow <gregn4422@gmail.com>

From: Greg Nancarrow <gregn4422@gmail.com>

To: Tomas Vondra <tomas.vondra@enterprisedb.com>

Cc: Dilip Kumar <dilipbalaut@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Euler Taveira <euler@eulerto.com>, Peter Smith <smithpb2250@gmail.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>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Amit Langote <amitlangote09@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>

Date: 2021-07-20T00:12:02Z

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 →

Release cache tuple when no longer needed
- ed0fbc8e5ac9 15.0 landed
Add some additional tests for row filters in logical replication.
- ceb57afd3ce1 15.0 landed
Fix one of the tests introduced in commit 52e4f0cd47.
- cfb4e209ec15 15.0 landed
Allow specifying row filters for logical replication of tables.
- 52e4f0cd472d 15.0 landed
Move scanint8() to numutils.c
- cfc7191dfea3 15.0 cited
Replace Test::More plans with done_testing
- 549ec201d613 15.0 cited
Reduce relcache access in WAL sender streaming logical changes
- 6ce16088bfed 15.0 cited
Small cleanups related to PUBLICATION framework code
- c9105dd3660f 15.0 cited
Add a view to show the stats of subscription workers.
- 8d74fc96db5f 15.0 cited
Allow publishing the tables of schema.
- 5a2832465fd8 15.0 cited
Doc: improve documentation of CREATE/ALTER SUBSCRIPTION.
- 1882d6cca161 15.0 cited
Add PublicationTable and PublicationRelInfo structs
- 0c6828fa987b 15.0 cited
Remove unused argument "txn" in maybe_send_schema().
- 93d573d86571 15.0 cited
Add prepare API support for streaming transactions in logical replication.
- 63cf61cdeb7b 15.0 cited
Unify PostgresNode's new() and get_new_node() methods
- 201a76183e20 15.0 cited
Use l*_node() family of functions where appropriate
- 2b00db4fb0c7 15.0 cited
Add support for prepared transactions to built-in logical replication.
- a8fd13cab0ba 15.0 cited
Restore the portal-level snapshot after procedure COMMIT/ROLLBACK.
- ef9480509622 11.13 cited
Rename a parse node to be more general
- 91d1f2d30210 14.0 landed
Remove unused column atttypmod from initial tablesync query
- 4ad31bb2ef25 14.0 landed
SEARCH and CYCLE clauses
- 3696a600e229 14.0 cited

On Mon, Jul 19, 2021 at 11:32 PM Tomas Vondra
<tomas.vondra@enterprisedb.com> wrote:
>
> I have a feeling it's getting overly complicated, to the extent that
> it'll be hard to explain to users and reason about. I don't think
> there's a "perfect" solution for cases when the filter expression gives
> different answers for old/new row - it'll always be surprising for some
> users :-(
>
> So maybe the best thing is to stick to the simple approach already used
> e.g. by pglogical, which simply user the new row when available (insert,
> update) and old one for deletes.
>
> I think that behaves more or less sensibly and it's easy to explain.
>
> All the other things (e.g. turning UPDATE to INSERT, advanced conflict
> resolution etc.) will require a lot of other stuff, and I see them as
> improvements of this simple approach.
>

+1
My thoughts on this are very similar.


Regards,
Greg Nancarrow
Fujitsu Australia