Re: PRIMARY KEY and UNIQUE

From: Darren Ferguson <darren(at)crystalballinc(dot)com>
To: Erwin Ambrosch <erwin(dot)ambrosch(at)ebutec(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: PRIMARY KEY and UNIQUE
Date: 2002-02-21 18:59:58
Message-ID: Pine.LNX.4.10.10202211359080.17552-100000@thread.crystalballinc.com
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No the unique constraint is not necessary because a primary key by
definition should be able to be used to uniquly define a row tuple
whatever it is called

Darren Ferguson

On Thu, 14 Feb 2002, Erwin Ambrosch wrote:

> Hi,
>
> I have a such a table.
>
> CREATE TABLE int_article (
> name VARCHAR(12) UNIQUE
> headline TEXT,
> summary TEXT,
> main TEXT,
> footer TEXT,
> PRIMARY KEY (name)
> );
>
> Is the UNIQUE constraint neccessary, because if have specified the column
> name to be the primary key.
>
> Thanks in advance
> Erwin
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>

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