RE: [External] Re: WAL Replication query

If replication is in asynchronous then there will be data loss, right Laurenz?

Thanks,
Sacheen Birhade.

-----Original Message-----
From: Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at>
Sent: Tuesday, November 1, 2022 12:11 PM
To: KK CHN <kkchn(dot)in(at)gmail(dot)com>; pgsql-admin(at)lists(dot)postgresql(dot)org
Subject: [External] Re: WAL Replication query

On Tue, 2022-11-01 at 11:25 +0530, KK CHN wrote:
> I am  trying  WAL replication,the setup is working  with a primary and Standby server.
>
> Query is  :   When the primary crashes  due an unforeseen reason, what
> may happen to the uncommitted transactions at primary ?

Their effects remain invisible.
  
> Those  won't replicate to the standby right ?

They may be replicated, but their effects will remain invisible there too.

> How much data loss occurs in this case ?

Data loss? I don't understand. There is no data loss with replication.
If an incomplete transaction is rolled back, that is no data loss.

> What is the mechanism to overcome this uncommitted transaction loss
> due to primary server crash which is not   replicated to the standby  server ?

I don't understand. Are you perhaps talking about failover?

Yours,
Laurenz Albe
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