Date: Wed, 9 Mar 2022 14:44:42 -0300
From: =?utf-8?Q?=C3=81lvaro?= Herrera <alvherre@alvh.no-ip.org>
To: Zhihong Yu <zyu@yugabyte.com>
Cc: Andres Freund <andres@anarazel.de>,
	"pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>,
	Simon Riggs <simon.riggs@enterprisedb.com>,
	Tomas Vondra <tomas.vondra@enterprisedb.com>,
	Daniel Westermann <dwe@dbi-services.com>,
	Amit Langote <amitlangote09@gmail.com>,
	Justin Pryzby <pryzby@telsasoft.com>,
	Japin Li <japinli@hotmail.com>, Erik Rijkers <er@xs4all.nl>,
	Jaime Casanova <jcasanov@systemguards.com.ec>
Subject: Re: support for MERGE
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On 2022-Mar-07, Zhihong Yu wrote:

> For v13-0003-MERGE-SQL-Command-following-SQL-2016.patch :
> 
> +    * Reset per-tuple memory context to free any expression evaluation
> +    * storage allocated in the previous cycle.
> +    */
> +   ResetExprContext(econtext);
> 
> Why is the memory cleanup done in the next cycle ? Can the cleanup be done
> at the end of the current cycle ?

I have removed that, because Andres had already pointed out that it was
redundant with the reset done in the caller.

> +            * XXX Should this explain why MERGE has the same logic as UPDATE?
> 
> I think explanation should be given.

Actually, the routine in question is only handling insert, not UPDATE,
so MERGE is not relevant to the function.  I have removed the comment.
This was probably a leftover from work prior to 86dc90056dfd; that
commit made it all irrelevant.

-- 
Álvaro Herrera              Valdivia, Chile  —  https://www.EnterpriseDB.com/
"Ninguna manada de bestias tiene una voz tan horrible como la humana" (Orual)