Re: trigger question

On Thu, 2002-05-16 at 12:49, Josh Berkus wrote:
> Larry,
>
> > Is there a way in PL/pgSQL to have a trigger look at the fields in a
> > %ROWTYPE variable to look for changes?
> >
> > I'm looking to be able to log the fields that are different between old
> > and new in a trigger, but don't want to have to list each field (It
> > changes, occasionally, but it changes). I'd also like to add a
> > timestamp and flag field when I store the record in the log table.
> >
> > Am I just SOL, or is there a way to do this? (7.2.1, if it matters).
>
> I'm pretty sure there is a way to do what you want, and it's probably simpler
> than you think.
>
> However, I need you to be more explicit, with examples. I can't quite figure
> out what is is you're trying to do.
>

given the following table:
CREATE TABLE "networks" (
"netblock" cidr,
"router" integer,
"interface" character varying(256),
"dest_ip" inet,
"mis_token" character(16),
"assigned_date" date,
"assigned_by" character varying(256),
"justification_now" integer,
"justification_1yr" integer,
"cust_asn" integer,
"comments" character varying(2048),
"other_reference" character varying(256),
"parent_asn" integer,
"status" integer NOT NULL,
"purpose" integer,
"last_update_by" character varying(256),
"last_update_at" timestamp with time zone,
"customer_reference" integer,
"natblock" cidr
);

I want to log the changes to it in a trigger. Occasionally we add fields to it, so
I'd like the trigger to know about them automatically. I need to log old/new for just the fields
that change (and the netblock, which is the primary key).

I realize I can build up the insert, but that seems to be the hard way.

> -Josh Berkus
--
Larry Rosenman http://www.lerctr.org/~ler
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