Re: Synchronizing slots from primary to standby

Hi,

On 11/27/23 9:57 AM, Zhijie Hou (Fujitsu) wrote:
> On Monday, November 27, 2023 4:51 PM shveta malik <shveta.malik@gmail.com> wrote:
> 
> Here is the updated version(v39_2) which include all the changes made in 0002.
> Please use for review, and sorry for the confusion.
> 

Thanks!

As far v39_2-0001:

"
     Altering the failover option of the subscription is currently not
     permitted. However, this restriction may be lifted in future versions.
"

Should we mention that we can alter the related replication slot?

+         <para>
+          The implementation of failover requires that replication
+          has successfully finished the initial table synchronization
+          phase. So even when <literal>failover</literal> is enabled for a
+          subscription, the internal failover state remains
+          temporarily <quote>pending</quote> until the initialization phase
+          completes. See column <structfield>subfailoverstate</structfield>
+          of <link linkend="catalog-pg-subscription"><structname>pg_subscription</structname></link>
+          to know the actual failover state.
+         </para>

I think we have a corner case here. If one alter the replication slot on the primary
then "subfailoverstate" is not updated accordingly on the subscriber. Given the 2 remarks above
would that make sense to prevent altering a replication slot associated to a subscription?

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com