Trigger function that works with both updates and deletes?

On Mon, Jun 18, 2007 at 06:07:37PM -0700, novnov wrote:

First, when a record is being deleted, OLD refers to the rec just deleted
(or about to be deleted)?

Correct.

Second, while I could write two trigger functions, one dealing with
add/update, the other with deletes, it's probably neater to have a single
trigger function and have it discriminate "am I being called for a delete,
or an add/update?" I don't know how to determine the type record change.

In PL/pgSQL you can use TG_OP. See "Trigger Procedures" in the
documentation:

http://www.postgresql.org/docs/8.2/interactive/plpgsql-trigger.html

--
Michael Fuhr

Second, while I could write two trigger functions, one dealing with
add/update, the other with deletes, it's probably neater to
have a single
trigger function and have it discriminate "am I being called
for a delete,
or an add/update?" I don't know how to determine the type
record change.

I use trigger arguments and determine what to do by:

if TG_ARGV[0] = 'value'
then
....
end if;

Allan

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Perfect, thanks

Michael Fuhr wrote:

On Mon, Jun 18, 2007 at 06:07:37PM -0700, novnov wrote:

First, when a record is being deleted, OLD refers to the rec just deleted
(or about to be deleted)?

Correct.

Second, while I could write two trigger functions, one dealing with
add/update, the other with deletes, it's probably neater to have a single
trigger function and have it discriminate "am I being called for a
delete,
or an add/update?" I don't know how to determine the type record change.

In PL/pgSQL you can use TG_OP. See "Trigger Procedures" in the
documentation:

http://www.postgresql.org/docs/8.2/interactive/plpgsql-trigger.html

--
Michael Fuhr

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