From: Jens Schipkowski <jens.schipkowski@apus.co.at>
To: Sven Geisler <sgeisler@aeccom.com>
To: pgsql-performance@postgresql.org
Subject: Re: single transaction vs multiple transactions
Date: Tue, 05 Dec 2006 16:45:25 +0100
Message-ID: <op.tj3fdzu081rjf6@xjens.apus.local> (raw)
In-Reply-To: <45758FBF.2030404@aeccom.com>
References: <45758FBF.2030404@aeccom.com>
Hi,
PostgreSQL offers some proprietary SQL parameters and commands which
easily solves such problems.
If you are sure PostgreSQL is the DB for your app forever ;) , you could
use this parameters and commands.
Here a possible resolution for your problem.
DELETE FROM x USING tmp WHERE x.y=tmp.z;
Please read the extensive documentation of PostgreSQL first, before
posting.
CU,
Jens
On Tue, 05 Dec 2006 16:26:55 +0100, Sven Geisler <sgeisler@aeccom.com>
wrote:
> Hi,
>
> I have to refactoring a 'DELETE FROM x WHERE y IN (...)' because IN got
> to much parameters. => 'stack depth limit exceeded'
> I don't want to increase just the parameter for max_stack_depth. It is
> better to refactoring because the number of arguments to IN may increase
> in the future.
>
> My approach is to do multiple 'DELETE FROM x WHERE y=...'.
>
> My question is now, what is better for PostgreSQL from a performance
> perspective?
> 1. all multiple deletes in one transaction
> 2. each delete in its own transaction
>
> The number of arguments is around 10,000.
>
> BTW: The arguments are generate in the application tier. I would have to
> create a temporary table which I can use in 'DELETE FROM x WHERE y IN
> (SELECT z FROM tmp)'.
>
> Cheers
> Sven
>
> ---------------------------(end of broadcast)---------------------------
> TIP 2: Don't 'kill -9' the postmaster
--
**
Dipl.-Designer Jens Schipkowski
APUS Software GmbH
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To: pgsql-performance@postgresql.org
Cc: jens.schipkowski@apus.co.at, sgeisler@aeccom.com
Subject: Re: single transaction vs multiple transactions
In-Reply-To: <op.tj3fdzu081rjf6@xjens.apus.local>
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