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Date: Wed, 08 Apr 2020 22:36:28 +0300
From: Anna Akenteva <a.akenteva@postgrespro.ru>
To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: a.korotkov@postgrespro.ru, i.kartyshov@postgrespro.ru,
 amit.kapila16@gmail.com, pgsql-hackers@lists.postgresql.org,
 tgl@sss.pgh.pa.us
Subject: Re: [HACKERS] make async slave to wait for lsn to be replayed
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On 2020-04-08 04:09, Kyotaro Horiguchi wrote:
> How about something like the follows.
> 
> BEGIN AFTER ColId Sconst
> BEGIN FOLOWING ColId Sconst
> 
> UNTIL <absolute time>;
> LIMIT BY <interval>;
> WITHIN Iconst;
> 
> regards.

I like your suggested keywords! I think that "AFTER" + "WITHIN" sound 
the most natural. We could completely give up the LSN keyword for now. 
The final command could look something like:

BEGIN AFTER ‘0/303EC60’ WITHIN '5 seconds';
or
BEGIN AFTER ‘0/303EC60’ WITHIN 5000;

I'd like to hear others' opinions on the syntax as well.

-- 
Anna Akenteva
Postgres Professional:
The Russian Postgres Company
http://www.postgrespro.com