Date: Mon, 19 Jul 2021 22:23:07 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Tomas Vondra <tomas.vondra@enterprisedb.com>
Cc: Dilip Kumar <dilipbalaut@gmail.com>,
	Amit Kapila <amit.kapila16@gmail.com>,
	Greg Nancarrow <gregn4422@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-19, Tomas Vondra wrote:

> I have a feeling it's getting overly complicated, to the extent that
> it'll be hard to explain to users and reason about. I don't think
> there's a "perfect" solution for cases when the filter expression gives
> different answers for old/new row - it'll always be surprising for some
> users :-(
> 
> So maybe the best thing is to stick to the simple approach already used
> e.g. by pglogical, which simply user the new row when available (insert,
> update) and old one for deletes.

OK, no objection to that plan.

-- 
Álvaro Herrera           39°49'30"S 73°17'W  —  https://www.EnterpriseDB.com/
"No es bueno caminar con un hombre muerto"