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Forum:
Visual FoxPro
Catégorie:
Codage, syntaxe et commandes
Titre:
Divers
Thread ID:
00171828
Message ID:
00171979
Vues:
35
Jim,
Surrogate keys remove the necessity of forcing users to enter a unique key. I've yet to find any user-entered primary key that they can't trash. Social Security? Some people don't have one. Phone number? Multiple people in the same household. Etc, etc. Surrogate keys aren't for ORDERING a table, they are meant to provide a consistent and unique entry to every record which can then be used for SQL insert/update commands and to link parent/child tables.

HTH
Barbara (Not a wunderkind)

>Hi Nancy,
>
>Frankly I have never figured out the purpose of surrogate primary keys. If you need a unique data order, a primary key is the way to go. If you don't need it, then stick with regular indices -- which are a lot easier to work with.
>
>I suspect I don't fully understand their (surrogate keys) utility. I'll have to get one of the wunderkinder to explain it to me sometime.
>
>Best wishes for a happy and successful new year,
>
>regards,
Barbara Paltiel, Paltiel Inc.
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