Subject: Re: Transaction Size in PostgreSQL
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From: Thomas Kellerer <shammat@gmx.net>
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Date: Tue, 7 Dec 2021 07:41:13 +0100
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Sivasamy Subramaniam schrieb am 07.12.2021 um 06:13:
> Transaction size meaning, for example - any transaction over 1GB in
> size? I am looking to set up an alert if any massive data changes are
> happening in a single transaction. I can do it for long running
> transactions or query but trying to figure out any easy way to
> calculate the amount of data changes per transaction.


A long running transaction doesn't necessary mean it wrote "1GB" of data,
and a transaction that writes 1GB of data isn't necessarily a "long runnin=
g"
transaction.

"Massive data changes" in a single transaction aren't really a problem.
In my experience a single transaction changing a lot of rows is more
efficient than multiple transactions changing fewer rows.

A long _running_ transaction - even if it only changed one row - is a much
bigger problem though.