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Date: Thu, 02 Feb 2006 15:19:26 +0100
From: Markus Schaber <schabi@logix-tt.com>
Organization: Logical Tracking and Tracing International AG, Switzerland
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To: Andrew Sullivan <ajs@crankycanuck.ca>
Cc: pgsql-sql@postgresql.org
Subject: Re: Changing the transaction isolation level within the	stored
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Hi, Andreq,

Andrew Sullivan wrote:

> I think you don't have a clear idea of what locks are necessary for
> updates.  Write operations on a row must block other write operations
> on the same row.  If more than one transaction needs the same kinds
> of locks on two different tables, but attempts to get those locks in
> the opposite order, you are all but guaranteed a deadlock.  MVCC
> helps, but it can't avoid locking the same data when that data is
> being updated.

You're right, I was mislead from my memory.

Sorry for the confusion I brought to this issue.

Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org