Message-ID: <88faef33e966796226022d6e7f3e32ad6c59fcfd.camel@cybertec.at>
Subject: Re: WAL Replication query
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: KK CHN <kkchn.in@gmail.com>, pgsql-admin@lists.postgresql.org
Date: Tue, 01 Nov 2022 07:41:11 +0100
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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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