Message-ID: <80949637-4e74-6c84-dc4d-908563dade29@dunslane.net>
Date: Thu, 7 Dec 2023 11:38:47 -0500
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Subject: Re: Make COPY format extendable: Extract COPY TO format
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To: Junwang Zhao <zhjwpku@gmail.com>, Michael Paquier <michael@paquier.xyz>
Cc: Sutou Kouhei <kou@clear-code.com>, nathandbossart@gmail.com,
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From: Andrew Dunstan <andrew@dunslane.net>
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On 2023-12-07 Th 03:37, Junwang Zhao wrote:
>
> The point of this refactor (from my view) is to make it possible to add new
> copy handlers in extensions, just like access method. As Andres suggested,
> a system catalog like *pg_copy_handler*, if we split TO and FROM into two
> sets of routines, does that mean we have to create two catalog(
> pg_copy_from_handler and pg_copy_to_handler)?


Surely not. Either have two fields, one for the TO handler and one for 
the FROM handler, or a flag on each row indicating if it's a FROM or TO 
handler.


cheers


andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com