Date: Wed, 30 Mar 2022 10:06:17 +0900 (JST)
Message-Id: <20220330.100617.1491348930290941094.horikyota.ntt@gmail.com>
To: er@xs4all.nl
Cc: boekewurm+postgres@gmail.com, pgsql-hackers@lists.postgresql.org
Subject: Re: TRAP: FailedAssertion("HaveRegisteredOrActiveSnapshot()",
 File: "toast_internals.c", Line: 670, PID: 19403)
From: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
In-Reply-To: <dbebe820-eec3-d643-aab7-26a33392c27b@xs4all.nl>
References: <20220329.181011.1401235917653600685.horikyota.ntt@gmail.com>
	<CAEze2Wgv4FNYjjtY13HzgC+affAXsSVJYiztrN149B6+O+zq7Q@mail.gmail.com>
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At Tue, 29 Mar 2022 13:29:15 +0200, Erik Rijkers <er@xs4all.nl> wrote in 
> Op 29-03-2022 om 12:50 schreef Matthias van de Meent:
> > An shorter (?) reproducer might be the following, which forces any
> > value for 'a' to be toasted and thus triggering the check in
> > init_toast_snapshot regardless of value length:
> > CREATE TABLE t (a text);
> > ALTER TABLE t ALTER COLUMN a SET STORAGE EXTERNAL;
> > INSERT INTO t VALUES ('toast');
> > BEGIN;
> > DECLARE c CURSOR FOR SELECT * FROM t;
> > FETCH ALL IN c;

Yeah, unfortunately I tried that first and saw it didn't work. And it
still doesn't for me.  With such a short text pg_detoast_datum_pakced
doesn't call detoast_attr.  Actually it is VARATT_IS_1B. (@master)

I think I'm missing something here. I'm going to examine around.

regards.

-- 
Kyotaro Horiguchi
NTT Open Source Software Center