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Date: Tue, 2 Aug 2016 13:31:17 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Cc: pgsql-docs <pgsql-docs@postgresql.org>
Subject: Re: NOTIFY man page still recommends rules
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Peter Eisentraut wrote:
> The NOTIFY man page writes
> 
>    When <command>NOTIFY</command> is used to signal the occurrence of
> changes
>    to a particular table, a useful programming technique is to put the
>    <command>NOTIFY</command> in a rule that is triggered by table updates.
> 
> Is using rules here still best practice?  This was probably written
> before statement triggers were available.
> 
> Even if yes, we might want to explain why, since we generally discourage
> rule use otherwise.

I think it's easier to dodge the rules topic entirely here and just
mention statement triggers.  Using rules you cannot cover the truncate
case, for instance.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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