Message-ID: <3bee08c2ca0fab15d14899afcb19490f29e0ec6f.camel@j-davis.com>
Subject: Re: alter table set TABLE ACCESS METHOD
From: Jeff Davis <pgsql@j-davis.com>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Michael Paquier <michael@paquier.xyz>, pgsql-hackers@postgresql.org,
 Jacob Champion <pchampion@vmware.com>, Heikki Linnakangas
 <hlinnaka@iki.fi>, Ashwin Agrawal <aagrawal@pivotal.io>,  Ashutosh Sharma
 <ashu.coek88@gmail.com>, Andres Freund <andres@anarazel.de>, Robert Haas
 <robertmhaas@gmail.com>,  Amit Kapila <amit.kapila16@gmail.com>, Alvaro
 Herrera <alvherre@alvh.no-ip.org>, Dilip Kumar <dilipbalaut@gmail.com>
Date: Thu, 06 May 2021 17:24:25 -0700
In-Reply-To: <20210506221943.GS27406@telsasoft.com>
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On Thu, 2021-05-06 at 17:19 -0500, Justin Pryzby wrote:
> If ATRewriteTable didn't
> handle this,
> data would become inaccessible if an AM failed to de-toast tuples.

If the AM fails to detoast tuples, it's got bigger problems than ALTER
TABLE. What about INSERT INTO ... SELECT?

It's the table AM's responsibility to detoast out-of-line datums and
toast any values that are too large (see
heapam.c:heap_prepare_insert()).

Regards,
	Jeff Davis