Re: row filtering for logical replication

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>
To: Dilip Kumar <dilipbalaut@gmail.com>
Cc: Euler Taveira <euler@eulerto.com>, Peter Smith <smithpb2250@gmail.com>, Greg Nancarrow <gregn4422@gmail.com>, "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, vignesh C <vignesh21@gmail.com>, "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>, Ajin Cherian <itsajin@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>, Amit Langote <amitlangote09@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-12-06T06:54:04Z
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 Mon, Dec 6, 2021 at 12:06 PM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>
> On Mon, Dec 6, 2021 at 6:49 AM Euler Taveira <euler@eulerto.com> wrote:
> >
> > On Fri, Dec 3, 2021, at 8:12 PM, Euler Taveira wrote:
> >
> > PS> I will update the commit message in the next version. I barely changed the
> > documentation to reflect the current behavior. I probably missed some changes
> > but I will fix in the next version.
> >
> > I realized that I forgot to mention a few things about the UPDATE behavior.
> > Regardless of 0003, we need to define which tuple will be used to evaluate the
> > row filter for UPDATEs. We already discussed it circa [1]. This current version
> > chooses *new* tuple. Is it the best choice?
>
> But with 0003, we are using both the tuple for evaluating the row
> filter, so instead of fixing 0001, why we don't just merge 0003 with
> 0001?
>

I agree that would be better than coming up with an entirely new
approach especially when the current approach is discussed and agreed
upon.

>  I mean eventually, 0003 is doing what is the agreed behavior,
> i.e. if just OLD is matching the filter then convert the UPDATE to
> DELETE OTOH if only new is matching the filter then convert the UPDATE
> to INSERT.

+1.

>  Do you think that even we merge 0001 and 0003 then also
> there is an open issue regarding which row to select for the filter?
>

I think eventually we should merge 0001 and 0003 to avoid any sort of
data consistency but it is better to keep them separate for the
purpose of a review at this stage. If I am not wrong that still needs
bug-fix we are discussing it as part of CF entry [1], right? If so,
isn't it better to review that bug-fix patch and the 0003 patch being
discussed here [2] to avoid missing any already reported issues in
this thread?

[1] - https://commitfest.postgresql.org/36/3162/
[2] - https://www.postgresql.org/message-id/CAHut%2BPtJnnM8MYQDf7xCyFAp13U_0Ya2dv-UQeFD%3DghixFLZiw%40mail.gmail.com

-- 
With Regards,
Amit Kapila.