Message-ID: <a2b1d633e39041d57f6d43e9e14d9fd1877a5e1c.camel@cybertec.at>
Subject: Re: BUG #18118: bug report for COMMIT AND CHAIN feature
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: evan.lx@alibaba-inc.com, pgsql-bugs@lists.postgresql.org
Date: Thu, 21 Sep 2023 08:41:20 +0200
In-Reply-To: <18118-4b72fcbb903aace6@postgresql.org>
References: <18118-4b72fcbb903aace6@postgresql.org>
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On Wed, 2023-09-20 at 09:31 +0000, PG Bug reporting form wrote:
> PostgreSQL version: 14.9
> Operating system:=C2=A0=C2=A0 centos7
> Description:=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=20
>=20
> COMMIT(280a408b48d5ee42969f981bceb9e9426c3a344c) provides a way to suppor=
t
> chained commits. During recent development, I found that it left a flaw.
>=20
> The defect can be reproduced as follows:
>=20
> START TRANSACTION ISOLATION LEVEL SERIALIZABLE; COMMIT;
> START TRANSACTION ISOLATION LEVEL REPEATABLE READ\; savepoint s\; COMMIT =
AND
> CHAIN;
> SHOW transaction_isolation; -- transaction is active at this point
> COMMIT;
>=20
> will get:
> postgres=3D*# SHOW transaction_isolation; -- transaction is active at thi=
s
> point
> =C2=A0 transaction_isolation
> -----------------------
> =C2=A0 serializable
> (1 row)

I tried to reproduce that and failed, both with v14 and v16.

For me, "transaction_isolation" is "repeatable read".

Yours,
Laurenz Albe