From: Robert Treat <xzilla@users.sourceforge.net>
To: Troels Arvin <troels@arvin.dk>
Cc: pgsql-sql@postgresql.org
Subject: Re: Immutable attributes?
Date: 01 Jul 2003 12:28:27 -0400
Message-ID: <1057076907.11365.411.camel@camel> (raw)
In-Reply-To: <pan.2003.07.01.09.59.23.580853@arvin.dk>
References: <pan.2003.07.01.09.59.23.580853@arvin.dk>
On Tue, 2003-07-01 at 05:59, Troels Arvin wrote:
> Hello,
>
> I have a table like this:
>
> create table test (
> "test_id" serial primary key,
> "created" timestamp with time zone
> default current_timestamp
> check(created = current_timestamp),
> "some_datum" int not null
> );
>
> My question concerns the "created" attribute: I want this to reflect when
> the tuple was craeated; and I want to make sure that the timestamp is not
> wrong. That will work with the above schema. However, I also want to make
> sure that the "crated" attribut for a tuple is not changed once it has
> been set.
>
> I'm thinking about implementing it through a trigger, but is there a
> better way to create such "immutable" attributes?
>
I don't know if it's "better", but this is one of the things people find
the RULE system really handy for. Check the docs, I believe there are
examples of this.
Robert Treat
--
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL
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To: pgsql-sql@postgresql.org
Cc: xzilla@users.sourceforge.net, troels@arvin.dk
Subject: Re: Immutable attributes?
In-Reply-To: <1057076907.11365.411.camel@camel>
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