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Date: Fri, 7 Jun 2024 08:15:56 -0700
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Subject: Re: Questions on logical replication
To: Koen De Groote <kdg.dev@gmail.com>
Cc: PostgreSQL General <pgsql-general@lists.postgresql.org>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 6/6/24 15:19, Koen De Groote wrote:
> I'll give them a read, though it might take a few weekends
> 
> Meanwhile, this seems to be what I'm looking for:
> 
>  From 
> https://www.postgresql.org/docs/current/warm-standby.html#STREAMING-REPLICATION-SLOTS <https://www.postgresql.org/docs/current/warm-standby.html#STREAMING-REPLICATION-SLOTS>
> 
> " Replication slots provide an automated way to ensure that the primary 
> does not remove WAL segments until they have been received by all 
> standbys, and that the primary does not remove rows which could cause a 
> recovery conflict 
> <https://www.postgresql.org/docs/current/hot-standby.html#HOT-STANDBY-CONFLICT> even when the standby is disconnected."
> 
> I'm reading that as: "if there is a replication slot, if the standby is 
> disconnected, WAL is kept"
> 
> And if we know WAL is kept in the "pg_wal" directory, that sounds like 
> it could slowly but surely fill up disk space.
> 
> 
> But again, I'll give them a read. I've read all of logical replication 
> already, and I feel like I didn't get my answer there.

It would be a good idea to provide an a fairly specific outline of what 
you are trying to achieve, then it would be easier for folks to offer 
suggestions on what to do or not to do.

> 
> Thanks for the help
> 
> 
> Regards,
> Koen De Groote

-- 
Adrian Klaver
adrian.klaver@aklaver.com