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Date: Sun, 10 Jun 2001 09:35:44 +0200
From: hubert depesz lubaczewski <depesz@depesz.pl>
To: al_nunes@ciclotecnologia.com.br
Cc: pgsql-docs@postgresql.org
Subject: Re: Trigger Documentation
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On Fri, 8 Jun 2001 11:55:08 -0300 (BRT)
al_nunes@ciclotecnologia.com.br wrote:

> What I need to do now is very simple, I want to make a trigger that
check
> if some text field is null. If it is, I want to record something on
> it. What I was trying (unsuccessfully):
> CREATE FUNCTION ins_ip() RETURNS OPAQUE AS '
> BEGIN
>  IF NEW.<field> ISNULL THEN
>   NEW.<field> := "something";
>    RETURN NEW;
> END;

you're missing two things.
1st. there should be end if
2nd. is should be NEW.<field> := ''something'';

btw. it's better to do it with "DEFAULT" statement in create table.

depesz

-- 
hubert depesz lubaczewski                          http://www.depesz.pl/
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