Re: autonomous transactions

From: Decibel! <decibel(at)decibel(dot)org>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Simon Riggs <simon(at)2ndquadrant(dot)com>, Neil Conway <neilc(at)samurai(dot)com>, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>, "Roberts, Jon" <Jon(dot)Roberts(at)asurion(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: autonomous transactions
Date: 2008-01-25 06:27:40
Message-ID: 20080125062740.GM37748@decibel.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Wed, Jan 23, 2008 at 05:50:02PM -0500, Tom Lane wrote:
> Simon Riggs <simon(at)2ndquadrant(dot)com> writes:
> >> From looking at how Oracle does them, autonomous transactions are
> >> completely independent of the transaction that originates them -- they
> >> take a new database snapshot. This means that uncommitted changes in the
> >> originating transaction are not visible to the autonomous transaction.
>
> > Oh! Recursion depth would need to be tested for as well. Nasty.
>
> Seems like the cloning-a-session idea would be a possible implementation
> path for these too.

Oracle has a feature where you can effectively save a session and return
to it. For example, if filling out a multi-page web form, you could save
state in the database between those calls. I'm assuming that they use
that capability for their autonomous transactions; save the current
session to the stack, clone it, run the autonomous transaction, then
restore the saved one.
--
Decibel!, aka Jim C. Nasby, Database Architect decibel(at)decibel(dot)org
Give your computer some brain candy! www.distributed.net Team #1828

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Florian Weimer 2008-01-25 10:50:41 plperl: Documentation on BYTEA decoding is wrong
Previous Message Robert Treat 2008-01-24 22:37:04 Re: autonomous transactions