Re: Does entity integrity imply entity identity?
From: Mr. Scott <do_not_reply_at_noone.com>
Date: Sun, 2 Aug 2009 01:10:08 -0400
Message-ID: <d8-dnUZOgP4sgujXnZ2dnUVZ_qKdnZ2d_at_giganews.com>
Date: Sun, 2 Aug 2009 01:10:08 -0400
Message-ID: <d8-dnUZOgP4sgujXnZ2dnUVZ_qKdnZ2d_at_giganews.com>
"Bob Badour" <bbadour_at_pei.sympatico.ca> wrote in message
news:4a7479f3$0$23783$9a566e8b_at_news.aliant.net...
> Mr. Scott wrote:
>
>> Since the entity integrity rule ensures that a relational table cannot
>> have any duplicate rows, does that imply that each row in a table maps to
>> a distinct entity?
>
> I am unfamiliar with an entity integrity rule. It sounds like some shit
> somone just made up to market ER diagrams.
>
> http://en.wikipedia.org/wiki/Codd's_12_rules
>
> The guaranteed access rule is sometimes called the logical identity rule.
Does that mean that entity integrity implies entity identity? Is logical identity the same thing as entity identity? Received on Sun Aug 02 2009 - 07:10:08 CEST