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Date: Tue, 15 Oct 2002 06:06:03 +0000
From: Brian Blaha <bblaha@umr.edu>
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To: pgsql-sql@postgresql.org
Subject: SQL function triggers
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I would like to write a function as a set of SQL statements, and then 
use that function
in a trigger. However, since triggers require a return type of opaque, 
and SQL functions
cannot return type opaque, this doesn't look possible. Am I missing 
something? The SQL
that I would expect to do this is below. Incidentally, on an insert, 
would the trigger fire
once, twice, or infinitely?

create table test(
a integer,
b integer
) without oids;

create function test_func( test.a%TYPE )
RETURNS ?????
AS
'update test set b = a where a = $1;'
language SQL
with (isstrict);

create trigger test_trig after update
on test for each row
execute procedure test_func( a );