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Re: What is the difference between UNIQUE and PRIMARY KEY?

From: Bart <Bart_at_opcomp.demon.co.uk>
Date: Wed, 11 Apr 2001 22:17:29 +0100
Message-ID: <987024225.10953.0.nnrp-14.9e985e86@news.demon.co.uk>

A primary key is, by definition, the primary key to a table and a table can have only one.

A primary key is not an index, although is usually has an associated index.

A table can have any number of unique indexes.

A foreign key can only reference a primary key.

<u518615722_at_spawnkill.ip-mobilphone.net> wrote in message news:l.987022508.1940429687@[198.138.198.252]...
> I searched against metalink and could not find the
> definition of unique index, could somebody help
> me out?
>
> Thanks
>
>
>
>
> --
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Received on Wed Apr 11 2001 - 16:17:29 CDT

Original text of this message

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