Re: Synchronizing slots from primary to standby

Hi,

On 11/27/23 1:23 PM, Zhijie Hou (Fujitsu) wrote:
> On Monday, November 27, 2023 8:05 PM Drouvot, Bertrand <bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>> Did not look in details but it looks like there is more to do here as
>> this is failing (with v39_2):
>>
>> "
>> postgres(at)primary: psql replication=database
>> psql (17devel)
>> Type "help" for help.
>>
>> postgres=# CREATE_REPLICATION_SLOT test_logical20 LOGICAL pgoutput
>> FAILOVER;
>> ERROR: syntax error
>
> I think the command you executed is of old syntax style, which was kept for
> compatibility with older releases. And I think we can avoid supporting new
> option for the old syntax as described in the original thread[1] of commit
> 0266e98. So, the "syntax error" is as expected IIUC.
>
> The new style command is like:
> CREATE_REPLICATION_SLOT test_logical20 LOGICAL pgoutput (FAILOVER);
>
> [1] https://www.postgresql.org/message-id/CA%2BTgmobAczXDRO_Gr2euo_TxgzaH1JxbNxvFx%3DHYvBinefNH8Q%40mail.gmail.com
>

Oh, I see, thanks for pointing out.

Well, not related to that thread but it seems weird to me that the backward
compatibility is done at the "option" level then.

I think it would make more sense to support all the options if the old
syntax is still supported.

For example, having

postgres=# CREATE_REPLICATION_SLOT test_logical2 LOGICAL pgoutput TWO_PHASE;

working fine but

CREATE_REPLICATION_SLOT test_logical3 LOGICAL pgoutput FAILOVER;

failing looks weird to me.

But that's probably out of this thread's context anyway.

Regards,

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