From: Iain <iain@mst.co.jp>
To: Mike Rylander <mrylander@gmail.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: implementing an out-of-transaction trigger
Date: Thu, 16 Sep 2004 11:02:25 +0900
Message-ID: <008c01c49b91$361e86f0$7201a8c0@mst1x5r347kymb> (raw)
References: <002f01c49ad0$9491e180$7201a8c0@mst1x5r347kymb>
<b918cf3d0409150903579bed18@mail.gmail.com>
Hi Mike,
Thanks, that's exactly what I was looking for.
A quick quote from the docs:
...if a NOTIFY is executed inside a transaction, the notify events are not
delivered until and unless the transaction is committed. ...if a listening
session receives a notification signal while it is within a transaction, the
notification event will not be delivered to its connected client until just
after the transaction is completed...
This is pretty good so far. Though, as far as I can tell, there is no way to
have the notify activate a pl/pgsql function directly. I'll still need to
write a client program to create a session and actually do the listening,
that is if I havn't missed anything else...
Thanks again,
Iain
----- Original Message -----
From: "Mike Rylander" <mrylander@gmail.com>
To: "Iain" <iain@mst.co.jp>
Cc: <pgsql-sql@postgresql.org>
Sent: Thursday, September 16, 2004 1:03 AM
Subject: Re: [SQL] implementing an out-of-transaction trigger
> >I've come across a situation where I'd like to use some kind of
> "out-of-transaction
> >trigger" to do some processing after changes to some tables, but
> without extending
> >the duration of the main transaction. Of course, it's important that
> the processing be
> >completed so it has to be, as far as possible, reliable and "safe". The
extra
> >processing should be completed within a reasonable time after the
original
> >transaction, but it needn't happen immediately.
>
> Check out
> http://www.postgresql.org/docs/7.4/static/sql-listen.html
> and
> http://www.postgresql.org/docs/7.4/static/sql-notify.html
>
> Then look at the Rules system for generating a NOTIFY:
> http://www.postgresql.org/docs/7.4/static/sql-createrule.html
>
> --miker
>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: iain@mst.co.jp, mrylander@gmail.com
Subject: Re: implementing an out-of-transaction trigger
In-Reply-To: <008c01c49b91$361e86f0$7201a8c0@mst1x5r347kymb>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox