On 8/27/25 05:09, Dimitrios Apostolou wrote:
On Wednesday 2025-08-27 00:54, Adrian Klaver wrote:
What are the pg_dump/pg_restore commands?
What are the Postgres versions involved?
Are they community versions of Postgres or something else?
What is the depduplication program?
Comments in line below.
Dump is from PostgreSQL 16, it's pg_dump writing to stdout:
pg_dump -v --format=custom --compress=none --no-toast-compression --
serializable-deferrable db_name | borg create ...
As you can see the backup (and deduplicating) program is borgbackup.
Ok, I use BorgBackup and it is fairly forgiving of normal changes.
FYI, if you ever want to use compression check out gzip --rsyncable, I
have found it plays well with Borg. For more information see:
https://beeznest.wordpress.com/2005/02/03/rsyncable-gzip/
Restore is in PostgreSQL 17:
I first create the empty tables by running the DDL commands in version
control to setup the database. And then I do pg_restore --data-only:
pg_restore -vvvv -j 8 -U db_owner -d db_name --schema=public --
section=data dump_file
If you are using only the --data section why not --data-only in the pg_dump?
Or is the pg_dump output used for other purposes?
Worth noting is that the above pg_restore goes through the WAL, i.e. all
writes are done by walwriter, not the backend directly.
Please explain the above further.
The problem occurs when you do the pg_dump after this restore, correct?
Is it the same pg_dump command as you show above?
Postgres is standard open source running on own server. It has a couple
of custom patches that shouldn't matter in this codepath.
For completeness and just in case they may affect the output what do the
patches do?
Thanks in advance,
Dimitris
--
Adrian Klaver
adrian.kla...@aklaver.com
