Path: ...!fu-berlin.de!uni-berlin.de!not-for-mail
From: Karsten Hilbert <Karsten.Hilbert@gmx.net>
Newsgroups: comp.lang.python
Subject: Re: psycopg2 positioning of .commit() (Posting On Python-List
 Prohibited)
Date: Mon, 9 Sep 2024 19:28:23 +0200
Lines: 23
Sender: <karsten.hilbert@gmx.net>
Message-ID: <mailman.2.1725902905.31645.python-list@python.org>
References: <Zty7ZCMwKQl4C4Id@hermes.hilbert.loc>
 <4a1b12fc-24b7-4c7e-b1f2-6ec9c5f341c2@aklaver.com>
 <ZtzDubguRDWXwV-t@hermes.hilbert.loc>
 <mailman.46.1725744071.2917.python-list@python.org>
 <lk4ajkFbbnrU1@mid.individual.net>
 <slrnvdr13p.4dt.jon+usenet@raven.unequivocal.eu>
 <vbl2ig$222n3$2@dont-email.me>
 <slrnvdtf24.4dt.jon+usenet@raven.unequivocal.eu>
 <vbmge5$2c7jr$1@dont-email.me>
 <slrnvdthpa.4dt.jon+usenet@raven.unequivocal.eu>
 <Zt8wN6CjIF8A-9d2@hermes.hilbert.loc>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: quoted-printable
X-Trace: news.uni-berlin.de /pFRVUewYLpbdH7Ri300TgsDxYOdVGn3sd0iFi5+S0kA==
Cancel-Lock: sha1:JILsCKGQI1qq07c+9KZYGAglkaY= sha256:B2FLKpxxCgc242VYLWrSWaUWL2dBP0GkE3RTgrBOBfE=
Return-Path: <karsten.hilbert@gmx.net>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
Authentication-Results: mail.python.org; dkim=pass
 reason="2048-bit key; unprotected key"
 header.d=gmx.net header.i=karsten.hilbert@gmx.net
 header.b=Va0ZPRU4; dkim-adsp=pass; dkim-atps=neutral
X-Spam-Status: OK 0.018
X-Spam-Evidence: '*H*': 0.96; '*S*': 0.00; 'salt': 0.04; 'thread':
 0.05; 'explicitly': 0.07; 'received:212.227': 0.07; 'cases.':
 0.09; 'gpg': 0.09; 'karsten': 0.09; 'schrieb': 0.09;
 'subject:Python': 0.12; '1713': 0.16; '2024': 0.16; 'commit':
 0.16; 'connection.': 0.16; 'pool': 0.16; 'received:212.227.15':
 0.16; 'writable': 0.16; 'python': 0.16; 'to:addr:python-list':
 0.20; 'exception': 0.22; 'returns': 0.22; 'code': 0.23;
 'anything': 0.25; 'perform': 0.26; 'execution': 0.32; 'right,':
 0.32; 'sep': 0.32; 'unless': 0.32; 'but': 0.32; 'header:In-Reply-
 To:1': 0.34; 'pending': 0.35; 'mon,': 0.36; 'using': 0.37; 'to.':
 0.39; 'should': 0.40; 'connection': 0.61; 'skip:o 10': 0.61;
 'received:212': 0.62; 'received:91': 0.62; 'true': 0.63;
 'transaction': 0.64; 'less': 0.65; 'back': 0.67; 'operations':
 0.68; 'sequence': 0.69; 'subject:List': 0.71; 'potentially': 0.76;
 'database': 0.80; 'jon': 0.84; 'subject: \n ': 0.84;
 'subject:Posting': 0.84; 'transactions': 0.84
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmx.net;
 s=s31663417; t=1725902903; x=1726507703; i=karsten.hilbert@gmx.net;
 bh=uNyKN4Kcj0rk6v1Pv8LMwz/KQ7xWWZuzqkdvxeoiBBI=;
 h=X-UI-Sender-Class:Date:From:To:Subject:Message-ID:References:
 MIME-Version:Content-Type:In-Reply-To:Content-Transfer-Encoding:
 cc:content-transfer-encoding:content-type:date:from:message-id:
 mime-version:reply-to:subject:to;
 b=Va0ZPRU4oQ3yNglIWPdZRYSVWF0mc1LW0m+Zgh+EbeCzmbWXMGmeirCQ05ertarL
 WCE9aHhPt+rjvSdygEqdLJgHF36hcS/jJ/EY6DvO4ogjxYaeOWNFUPgJagSWqfTLS
 1vfRwWK3UMx5DWTaNZw+KfhMmXGL7W2iO+ia7Nw+ORZCCAprmb3oZsKsGUMV8FF5G
 a8PTa6xum3NMo3UKyba2TplnpgERY+1CfduMTfJyIOfg/zJ8VtETvuJcxPfvU7Jbv
 WMBW7SFMwS+tjxlnZ3ym9gmZrmTPvWNXuYpOGVY5WB7kuApFBBZPyyQuJ4Jxk2pHq
 pPBlw79fPuwurjNL1w==
X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a
Content-Disposition: inline
In-Reply-To: <slrnvdthpa.4dt.jon+usenet@raven.unequivocal.eu>
Ma_X_il-Followup-to: d
Re_X_turn-receipt-to: Karsten.Hilbert@gmx.net
Di_X_sposition-Notification-To: Karsten.Hilbert@gmx.net
X-Confi_X_rm-Reading-To: Karsten.Hilbert@gmx.net
X-Pri_X_ority: 2 (High)
X-Provags-ID: V03:K1:zyigGRiVikJ+iRzhIbri4MdHaWtZW/I3jnZoldz+chDO933E6HX
 ynO33PySaR39ot5rwN5Sb7287T/tlsT/jmaXko+Rt4Lzik25a3kFKTrEBXSJS42SVHPI3fc
 NmgQgjgTsqGCXUE7C5DHqVmBj/szXCOTB+PIeUeT4EWpYHD+PV94vD1dGyIxEYw6iUIoE7f
 2e+58Co4PUfh8DuNoOykA==
X-Spam-Flag: NO
UI-OutboundReport: notjunk:1;M01:P0:o2DGJEsi3O0=;kWbXCO5vIQIFjyBL/BzggxHscph
 A+v/kdyPoz9dnfoHGqruvHcecUX9U2y0BpypomY1hfIIhHtaFop4bMaxcLm7zG4iHAzwS5Kg2
 zxqAlXZnnZwtALQlt+GG9FUOdMfowuhNy9TybfwuOlF8IWXV3Fq+4Sovbd26dlaDCdbtcEgDs
 UF+mbHELnrU6po7p5hqH6ezrQGx/dItUhYFYm4f94n3qJU1qr4G6JAN6LGppFAMdtEKzr8ugQ
 n3r4UYuk9oeZk4uT2B5LXhszZUa/n8bt5Ixlev+NAFtFQZ/NkziRof8bTfv377uXJlyCBPtGs
 O8+YAYU5tIUUjUCOuh5FGoiTlwRj5DQjNomu6YjPrS49COUhsCcc33VuSTe5pLM88zEYdwQ4i
 DGdyKK+d78plp/YqmgTZTGY37XL/4yqUlpv2JU+SZryyXpGEejIYScVtp7iTjURie/PQRvPMN
 DjsVassxwMWCQc3wlkIlv5ghpcBtxasCpzaPicRTQJUgz0ZpLT2zdwlrbYIAm/oGvOlxCElKQ
 TdkzI0naEZa6S/yk4El55fdH9P7Ro7lCjBcGG5g8kKxtSX93XzACqMgbmJN8bzSrEVoG9DsPv
 SkKfHL3FHiGDE5l40rxFSO+zwqdcGGS+M7Fa3E326KclCCRQqkLIXajwN7YHbG3l5G9/yLZjj
 8YkBvPw5zobbVMDsAY25SmbjY5PVRlmVsm4BlxpPm82Xa/DkKzKf30cT7CCLciMd+qyPuDXPg
 AN3x3z8CDwldqcZ+A+QvdXhTfysac2r7sYK8/XVyV30IQqX+fOyE5C5sImnyaXEhohxLcVX34
 BWF9dvEUEi3Yzto2/k5YVuWw==
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: General discussion list for the Python programming language
 <python-list.python.org>
List-Unsubscribe: <https://mail.python.org/mailman/options/python-list>,
 <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <https://mail.python.org/pipermail/python-list/>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <https://mail.python.org/mailman/listinfo/python-list>,
 <mailto:python-list-request@python.org?subject=subscribe>
X-Mailman-Original-Message-ID: <Zt8wN6CjIF8A-9d2@hermes.hilbert.loc>
X-Mailman-Original-References: <Zty7ZCMwKQl4C4Id@hermes.hilbert.loc>
 <4a1b12fc-24b7-4c7e-b1f2-6ec9c5f341c2@aklaver.com>
 <ZtzDubguRDWXwV-t@hermes.hilbert.loc>
 <mailman.46.1725744071.2917.python-list@python.org>
 <lk4ajkFbbnrU1@mid.individual.net>
 <slrnvdr13p.4dt.jon+usenet@raven.unequivocal.eu>
 <vbl2ig$222n3$2@dont-email.me>
 <slrnvdtf24.4dt.jon+usenet@raven.unequivocal.eu>
 <vbmge5$2c7jr$1@dont-email.me>
 <slrnvdthpa.4dt.jon+usenet@raven.unequivocal.eu>
Bytes: 6978

Am Mon, Sep 09, 2024 at 10:00:11AM -0000 schrieb Jon Ribbens via Python-li=
st:

> > The database only needs to commit when it is explicitly told. Anything
> > less -- no commit.
>
> So the Python code is half-way through a transaction when it throws
> a (non-database-related) exception and that thread of execution is
> aborted. The database connection returns to the pool, and is re-used
> by another thread which continues using it to perform a different
> sequence of operations ... ending in a COMMIT, which commits
> one-and-a-half transactions.

Right, but that's true only when writable connections are
being pooled, which should be avoidable in many cases.

Any pool worth its salt should rollback any potentially
pending transactions of a connection when it is given back
that pooled connection. Unless explicitely told not to.

Karsten
=2D-
GPG  40BE 5B0E C98E 1713 AFA6  5BC0 3BEA AC80 7D4F C89B