Re: Triggers on transaction? - Mailing list pgsql-hackers

From Andreas Joseph Krogh
Subject Re: Triggers on transaction?
Date
Msg-id VisenaEmail.bf.c8a67230d3d08146.14d956f18d1@tc7-visena
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In response to Re: Triggers on transaction?  (Marko Tiikkaja <marko@joh.to>)
Responses Re: Triggers on transaction?  (Glyn Astill <glynastill@yahoo.co.uk>)
List pgsql-hackers
På onsdag 27. mai 2015 kl. 12:42:29, skrev Marko Tiikkaja <marko@joh.to>:
On 5/27/15 12:39 PM, Jordan Gigov wrote:
> I found myself in need of triggers that are run only once per transaction,
> rather than per row or statement within the transaction. Meaning it will
> always be deferred and never called twice for the same transaction.

What's the use case?
 
 
I've often needed this for stuff like:
 
UPDATE some_table SET col = 'foo' where id = 1;
UPDATE some_table SET col = 'bar' where id = 1;
 
I want the "on-tx"-trigger to only run once, and on the last update of "col" so that it sees 'bar'.
 
--
Andreas Joseph Krogh
CTO / Partner - Visena AS

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