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Message-ID: <7cb50df2-9c76-477f-91c9-e149c7637104@aklaver.com>
Date: Sat, 7 Sep 2024 09:46:03 -0700
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Subject: Re: psycopg2: proper positioning of .commit() within try: except:
 blocks
To: Karsten Hilbert <Karsten.Hilbert@gmx.net>, psycopg@lists.postgresql.org
Cc: python-list@python.org
References: <Ztx1sZMGTnA3eLP1@hermes.hilbert.loc>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <Ztx1sZMGTnA3eLP1@hermes.hilbert.loc>
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On 9/7/24 08:48, Karsten Hilbert wrote:
> Dear all,
> 
> unto now I had been thinking this is a wise idiom (in code
> that needs not care whether it fails to do what it tries to
> do^1):
> 
> 	conn = psycopg2.connection(...)

In the above do you have:

https://www.psycopg.org/docs/extensions.html#psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE

psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE

Or is that in some other concurrent transaction?

> 	curs = conn.cursor()
> 	try:
> 		curs.execute(SOME_SQL)
> 	except PSYCOPG2-Exception:
> 		some logging being done, and, yes, I
> 		can safely inhibit propagation^1
> 	finally:
> 		conn.commit()		# will rollback, if SOME_SQL failed

It will if you use with conn:, otherwise it up to you to do the rollback()

Are you are doing a rollback() in except PSYCOPG2-Exception: ?


-- 
Adrian Klaver
adrian.klaver@aklaver.com