From: Chris Browne <cbbrowne@acm.org>
Subject: Re: trigger for TRUNCATE?
Date: Tue, 08 Jan 2008 15:57:21 -0500
Organization: cbbrowne Computing Inc
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Message-ID: <60tzloyr0u.fsf@dba2.int.libertyrms.com>
References: <4783BEA9.3020507@fmed.uba.ar>
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To: pgsql-sql@postgresql.org

gherzig@fmed.uba.ar (Gerardo Herzig) writes:
> Hi all. Acording to the docs, TRUNCATE will not fire a DELETE trigger
> on the table being truncated.
> There is a way to capture a TRUNCATE in any way?

I think there's some sort of "to do" on that...

It ought to be not *too* difficult (I imagine!) to be able to
associate a trigger with the TRUNCATE action, and therefore run some
stored function any time TRUNCATE takes place.

For the Slony-I replication system, it would be attractive for this to
lead to attaching two functions:
  - One function would return an exception so that TRUNCATE against
    a subscriber node would fail...

  - Another would pretty much be as simple as submitting an event;
    perform createEvent('_ourcluster', 'TRUNCATE_TABLE', table_id);

A new event, TRUNCATE_TABLE, would do a TRUNCATE against the
subscribers.

This represents a pretty easy enhancement, given the new kind of
trigger.
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