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Date: Wed, 14 Aug 2002 08:09:36 -0400
From: "Raymond Chui" <Raymond.Chui@noaa.gov>
Organization: NWS NOAA
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To: pgsql-sql@postgresql.org, pgadmin-support@postgresql.org,
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Subject: How to execute my trigger when update certain columns but not all?
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Let say I have a table has column1 and column2 and I made a trigger for
after INSERT OR UPDATE for each row to execute procedure my_function.

What I want is the trigger execute my_function only when column1 is
insert or
update, but not going to execute my_function when column2 is insert or
update.
How do I do that?

Thank Q very much

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