Re: Strategy for Primary Key Generation When Populating Table

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От Rich Shepard
Тема Re: Strategy for Primary Key Generation When Populating Table
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Msg-id alpine.LNX.2.00.1202091625510.5256@salmo.appl-ecosys.com
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Ответ на Re: Strategy for Primary Key Generation When Populating Table  (Merlin Moncure <mmoncure@gmail.com>)
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On Thu, 9 Feb 2012, Merlin Moncure wrote:

> If you can't (which happens on various type of data), then the surrogate
> is giving the illusion of row uniqueness when there isn't one.

   Ah, but each row is unique. However, there is no consisten set of non NULL
values that can consistently define a unique key for each row.

Rich

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