Message-ID: <6c5d98c6-879d-690c-b769-96aa162b93d9@enterprisedb.com>
Date: Fri, 17 Dec 2021 10:53:48 +0100
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Subject: Re: Skipping logical replication transactions on subscriber side
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To: Greg Nancarrow <gregn4422@gmail.com>,
 Masahiko Sawada <sawada.mshk@gmail.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>,
 "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>,
 vignesh C <vignesh21@gmail.com>,
 "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>,
 "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>,
 Alexey Lesovsky <lesovsky@gmail.com>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
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From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
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On 13.12.21 04:12, Greg Nancarrow wrote:
> (ii) "Setting -1 means to reset the transaction ID"
> 
> Shouldn't it be explained what resetting actually does and when it can
> be, or is needed to be, done? Isn't it automatically reset?
> I notice that negative values (other than -1) seem to be regarded as
> valid - is that right?
> Also, what happens if this option is set multiple times? Does it just
> override and use the latest setting? (other option handling errors out
> with errorConflictingDefElem()).
> e.g. alter subscription sub skip (xid = 721, xid = 722);

Let's not use magic numbers and instead use a syntax that is more 
explicit, like SKIP (xid = NONE) or RESET SKIP or something like that.