Horton

Re: Support logical replication of DDLs

shveta malik <shveta.malik@gmail.com>

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From: shveta malik <shveta.malik@gmail.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>, vignesh C <vignesh21@gmail.com>, Ajin Cherian <itsajin@gmail.com>, "Wei Wang (Fujitsu)" <wangw.fnst@fujitsu.com>, Runqi Tian <runqidev@gmail.com>, Peter Smith <smithpb2250@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, li jie <ggysxcq@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Masahiko Sawada <sawada.mshk@gmail.com>, Japin Li <japinli@hotmail.com>, rajesh singarapu <rajesh.rs0541@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Zheng Li <zhengli10@gmail.com>, shveta malik <shveta.malik@gmail.com>
Date: 2023-05-02T03:00:51Z
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. Add a run_as_owner option to subscriptions.

  2. Refactor pgoutput_change().

  3. Print the correct aliases for DML target tables in ruleutils.

  4. Fix object identity string for transforms

  5. Add grantable MAINTAIN privilege and pg_maintain role.

  6. Get rid of recursion-marker values in enum AlterTableType

  7. Release cache tuple when no longer needed

  8. Empty search_path in logical replication apply worker and walsender.

  9. Refactor format_type APIs to be more modular

  10. Use wrappers of PG_DETOAST_DATUM_PACKED() more.

On Fri, Apr 28, 2023 at 5:11 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Tue, Apr 25, 2023 at 9:28 AM Zhijie Hou (Fujitsu)
> <houzj.fnst@fujitsu.com> wrote:
> >
>
> I have a few high-level comments on the deparsing approach used in the
> patch. As per my understanding, we first build an ObjTree from the DDL
> command, then convert the ObjTree to Jsonb which is then converted to
> a JSON string.  Now, in the consecutive patch, via publication event
> triggers, we get the JSON string via the conversions mentioned, WAL
> log it, which then walsender will send to the subscriber, which will
> convert the JSON string back to the DDL command and execute it.
>
> Now, I think we can try to eliminate this entire ObjTree machinery and
> directly from the JSON blob during deparsing. We have previously also
> discussed this in an email chain at [1]. I think now the functionality
> of JSONB has also been improved and we should investigate whether it
> is feasible to directly use JSONB APIs to form the required blob.

+1.
I will investigate this and will share my findings.

thanks
Shveta