Re: row filtering for logical replication

Euler Taveira <euler@eulerto.com>

From: "Euler Taveira" <euler@eulerto.com>

To: Önder Kalacı <onderkalaci@gmail.com>

Cc: 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: 2021-02-22T12:28:07Z

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, Feb 22, 2021, at 7:45 AM, Önder Kalacı wrote:
> Thanks for working on this. I did some review and testing, please see my comments below.
I appreciate your review. I'm working on a new patch set and expect to post it soon.

> I think if you are planning to keep the debug patch, there seems to be an area of improvement in the following code:
I was not planning to include the debug part, however, it would probably help to  
debug some use cases. In the "row [not] matched" message, it should be DEBUG3  
for a final version because it is too noisy. Since you mentioned I will inspect
and include in the main patch those DEBUG messages that could possibly be      
useful for debug purposes.

> 
> 4) In terms of performance, I also separately verified that the overhead seems pretty low with the final patch. I used the tests in commands_to_perf_test.sql file which I shared earlier. The steps in the file do not intend to measure the time precisely per tuple, but just to see if there is any noticeable regression while moving lots of data. The difference between (a) no filter (b) simple filter is between %1-%4, which could even be considered in the noise level.
I'm concerned about it too, I'm currently experimenting alternatives to reduce this overhead.

> 5) I guess we can by-pass the function limitation via operators. Do you see anything problematic with that? I think that should be allowed as it helps power users to create more complex replications if they need.
Yes, you can. I have to check if this user-defined operator could possibly         
break the replication. I will make sure to include a test covering this case      
too.


--
Euler Taveira
EDB   https://www.enterprisedb.com/