Syntax on BEFORE Trigger - Cascade?

Good Morning,

We have a table - I'll call it *import_job* (which is the actual name) -
that lists jobs to be executed. Each job has one or more child components
listed in another table called *import_file*.

The child table has a foreign key column called *import_job_oid*
referencing the primary key in *import_file*.

When a record in *import_job* is deleted, the child records (file records)
in *import_file* need to be deleted first.

The constraint in both Oracle and Postgres is similar (Postgres version):
*ALTER TABLE IF EXISTS idev.import_file*

* ADD CONSTRAINT fk1_import_file FOREIGN KEY (import_job_oid)
REFERENCES idev.import_job (oid) MATCH SIMPLE ON UPDATE NO ACTION ON
DELETE CASCADE;*

The files are appropriately deleted in Oracle, but Postgres is returning
the following:
*ERROR: Attempt to suppress referential action with before trigger.
CONTEXT: SQL statement "DELETE FROM ONLY "idev"."import_file" WHERE $1
OPERATOR(pg_catalog.=) "import_job_oid"" *

There aren't any delete triggers for either table. Any idea why this isn't
working? Does cascade function differently in Postgres? Read the docs,
Googled the heck out of this and played all sorts of games with the tables.
I've also tried creating a before trigger on import_job, but can't seem to
get the right syntax for taking the oid from the psql delete picked up by
the trigger.

Here is one of my (many) attempts (have tried describing, setting, using
new.oid, old.oid, a bunch of stuff) and can't get this right either:

*CREATE OR REPLACE FUNCTION idev."td_import_job$import_job"() ** RETURNS
trigger ** LANGUAGE 'plpgsql' ** VOLATILE NOT LEAKPROOF **AS $BODY$ * *BEGIN
** RAISE NOTICE 'Value %', new.oid ** DELETE FROM idev.import_file ** WHERE
import_job_oid = new.oid; **RETURN OLD; **END; **$BODY$; * *delete from
idev.import_job where oid = 44949; * *NOTICE: Value <NULL> * *ERROR:
Attempt to suppress referential action with before trigger. *
*CONTEXT: SQL statement "DELETE FROM ONLY "idev"."import_file" WHERE $1
OPERATOR(pg_catalog.=) "import_job_oid" *

--

*David A. Barbour*

*dbarbour@istation.com <dbarbour@istation.com>*

*(214) 292-4096*

Istation

8150 North Central Expressway, Suite 2000

Dallas, TX 75206

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