Date: Fri, 12 Nov 2021 20:13:10 -0300
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Zhihong Yu <zyu@yugabyte.com>
Cc: Pg Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: support for MERGE
Message-ID: <202111122313.fjhecfq6yi2v@alvherre.pgsql>
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On 2021-Nov-12, Zhihong Yu wrote:

> Hi,
> 
> +           skipped_path = total - insert_path - update_path - delete_path;
> 
> Should there be an assertion that skipped_path is not negative ?

Hm, yeah, added.

> +    * We maintain separate transaction tables for UPDATE/INSERT/DELETE since
> +    * MERGE can run all three actions in a single statement. Note that UPDATE
> +    * needs both old and new transition tables
> 
> Should the 'transaction' in the first line be transition ?

Oh, of course.

Uploaded fixup commits to
https://github.com/alvherre/postgres/commits/merge-15

-- 
Álvaro Herrera              Valdivia, Chile  —  https://www.EnterpriseDB.com/