Horton

Re: Logical replication support for generic wal record

Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>

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From: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
To: Natarajan R <nataraj3098@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2022-08-22T06:45:45Z
Lists: pgsql-hackers 
On Mon, Aug 22, 2022 at 11:59 AM Natarajan R <nataraj3098@gmail.com> wrote:
>
> Hi All,
>
> I am writing a postgres extension which writes only generic wal record, but this wal is not recognized by logical replication decoder. I have a basic understanding of how logical replication(COPY command for initial sync, wal replica for final sync) works, can you please tell us a way to support this?

"Generic" resource manager doesn't have a decoding API, see [1], which
means that the generic WAL records will not get decoded.

Can you be more specific about the use-case? Why use only "Generic"
type WAL records? Why not use "LogicalMessage" type WAL records if you
want your WAL records to be decoded?

[1] https://github.com/postgres/postgres/blob/master/src/include/access/rmgrlist.h#L48

-- 
Bharath Rupireddy
RDS Open Source Databases: https://aws.amazon.com/rds/postgresql/

Commits

  1. Fix doc oversight for custom WAL resource managers.

  2. Custom WAL Resource Managers.