Date: Wed, 14 Jul 2021 10:01:05 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Dilip Kumar <dilipbalaut@gmail.com>
Cc: Tomas Vondra <tomas.vondra@enterprisedb.com>,
	Amit Kapila <amit.kapila16@gmail.com>,
	Euler Taveira <euler@eulerto.com>,
	Peter Smith <smithpb2250@gmail.com>,
	Rahila Syed <rahilasyed90@gmail.com>,
	Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
	=?utf-8?B?w5ZuZGVyIEthbGFjxLE=?= <onderkalaci@gmail.com>,
	japin <japinli@hotmail.com>, Michael Paquier <michael@paquier.xyz>,
	David Steele <david@pgmasters.net>,
	Craig Ringer <craig@2ndquadrant.com>,
	Tomas Vondra <tomas.vondra@2ndquadrant.com>,
	Amit Langote <amitlangote09@gmail.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: row filtering for logical replication
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On 2021-Jul-14, Dilip Kumar wrote:

> I think for insert we are only allowing those rows to replicate which
> are matching filter conditions, so if we updating any row then also we
> should maintain that sanity right? That means at least on the NEW rows
> we should apply the filter, IMHO.  Said that, now if there is any row
> inserted which were satisfying the filter and replicated, if we update
> it with the new value which is not satisfying the filter then it will
> not be replicated,  I think that makes sense because if an insert is
> not sending any row to a replica which is not satisfying the filter
> then why update has to do that, right?

Right, that's a good aspect to think about.

I think the guiding principle for which tuple to use for the filter is
what is most useful to the potential user of the feature, rather than
what is the easiest to implement.

-- 
Álvaro Herrera              Valdivia, Chile  —  https://www.EnterpriseDB.com/
"La libertad es como el dinero; el que no la sabe emplear la pierde" (Álvarez)