From: Richard Huxton <dev@archonet.com>
To: Andrei Bintintan <klodoma@ar-sd.net>
Cc: pgsql-sql@postgresql.org
Subject: Re: UNIQUE columnt depdening on other column???
Date: Wed, 02 Jun 2004 13:21:53 +0100
Message-ID: <40BDC661.6070305@archonet.com> (raw)
In-Reply-To: <20040602113937.D45E11765F@ar-sd.net>
References: <20040602113937.D45E11765F@ar-sd.net>
Andrei Bintintan wrote:
> Hi,
>
> I have a problem.
>
> Let's say I have the following table:
> CREATE TABLE rekl_element(
> id serial PRIMARY KEY,
> active boolean NOT NULL DEFAULT 'y',
> num int4 NOT NULL,
> text varchar(10)
> );
>
> Now I want that "num" column is "unique" but only for those columns that
> have active='y'. For the columns that have active='f' I don't care if num is
> unique or not. I'm asking this because num will be doubled some times.
Non-standard but elegant:
CREATE UNIQUE INDEX my_partially_unique_index ON rekl_element (num)
WHERE active;
--
Richard Huxton
Archonet Ltd
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To: pgsql-sql@postgresql.org
Cc: dev@archonet.com, klodoma@ar-sd.net
Subject: Re: UNIQUE columnt depdening on other column???
In-Reply-To: <40BDC661.6070305@archonet.com>
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