Re: Support logical replication of DDLs

Dilip Kumar <dilipbalaut@gmail.com>

From: Dilip Kumar <dilipbalaut@gmail.com>

To: Zheng Li <zhengli10@gmail.com>

Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, rajesh.rs0541@gmail.com

Date: 2022-03-21T08:13:34Z

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 →

Add a run_as_owner option to subscriptions.
- 482675987bcd 16.0 cited
Refactor pgoutput_change().
- da324d6cd45b 16.0 cited
Print the correct aliases for DML target tables in ruleutils.
- df931e9ab35b 11.20 landed
- c8a5f1685fb7 15.3 landed
- 4efb4f0d4878 13.11 landed
- 3dd287c14fac 12.15 landed
- 393430f57544 16.0 landed
- 14345f3c6a7b 14.8 landed
Fix object identity string for transforms
- 9a312562314a 16.0 landed
Add grantable MAINTAIN privilege and pg_maintain role.
- 60684dd834a2 16.0 cited
Get rid of recursion-marker values in enum AlterTableType
- 840ff5f451cd 16.0 cited
Release cache tuple when no longer needed
- ed0fbc8e5ac9 15.0 cited
Empty search_path in logical replication apply worker and walsender.
- 11da97024abb 14.0 cited
Refactor format_type APIs to be more modular
- a26116c6cbf4 11.0 cited
Use wrappers of PG_DETOAST_DATUM_PACKED() more.
- 3a0d473192b2 10.0 cited

On Thu, Mar 17, 2022 at 2:47 AM Zheng Li <zhengli10@gmail.com> wrote:
>
> Hi,
>
> >If you don't mind, would you like to share the POC or the branch for this work?
>
> The POC patch is attached. It currently supports the following functionalities:

Thanks for sharing, I will look into it.

> >In such cases why don't we just log the table creation WAL for DDL
> >instead of a complete statement which creates the table and inserts
> >the tuple? Because we are already WAL logging individual inserts and
> >once you make sure of replicating the table creation I think the exact
> >data insertion on the subscriber side will be taken care of by the
> >insert WALs no?
>
> The table creation WAL and table insert WAL are available. The tricky
> part is how do we break down this command into two parts (a normal
> CREATE TABLE followed by insertions) either from the parsetree or the
> WALs. I’ll have to dig more on this.

I agree that this is a bit tricky, anyway I will also put more thoughts on this.

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com