From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alessandro Baretta <a.baretta@barettadeit.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Suspending SELECTs
Date: Mon, 16 Jan 2006 14:57:38 -0300
Message-ID: <20060116175738.GB32100@surnet.cl> (raw)
In-Reply-To: <9766.1137433907@sss.pgh.pa.us>
References: <43CB71AC.20203@barettadeit.com>
<9766.1137433907@sss.pgh.pa.us>
Tom Lane wrote:
> Alessandro Baretta <a.baretta@barettadeit.com> writes:
> > I am aware that what I am dreaming of is already available through
> > cursors, but in a web application, cursors are bad boys, and should be
> > avoided. What I would like to be able to do is to plan a query and run
> > the plan to retreive a limited number of rows as well as the
> > executor's state. This way, the burden of maintaining the cursor "on
> > hold", between activations of the web resource which uses it, is
> > transferred from the DBMS to the web application server,
>
> This is a pipe dream, I'm afraid, as the state of a cursor does not
> consist exclusively of bits that can be sent somewhere else and then
> retrieved.
I wonder if we could have a way to "suspend" a transaction and restart
it later in another backend. I think we could do something like this
using the 2PC machinery.
Not that I'm up for coding it; just an idea that crossed my mind.
--
Alvaro Herrera Developer, http://www.PostgreSQL.org
Oh, oh, las chicas galacianas, lo harán por las perlas,
¡Y las de Arrakis por el agua! Pero si buscas damas
Que se consuman como llamas, ¡Prueba una hija de Caladan! (Gurney Halleck)
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To: pgsql-performance@postgresql.org
Cc: alvherre@alvh.no-ip.org, tgl@sss.pgh.pa.us, a.baretta@barettadeit.com
Subject: Re: Suspending SELECTs
In-Reply-To: <20060116175738.GB32100@surnet.cl>
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