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From: Erika Grondzakova <Erika.Grondzakova@cern.ch>
Newsgroups: comp.databases.oracle.server
Subject: Dilemma in choosing the candidate for the primary key.
Date: Wed, 28 Apr 1999 15:38:54 +0200
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Hello,

I'm making a new DB design. In the previous version of this DB, several
tables had as a primary key the column - name of the element from the
table. This column was VARCHAR2(16) and was unique. In the table there
wasn't another suitable number column.

In a new design I would create a new number column - sequence (maintain
it in the trigger) to define the primary key. My feeling is that it
would require less storage space in the index and as a foreign keys.

Does anybody has such as dilemma to choose PK canditate from the natural
column or to add one artificial? Do you have some experience in chossing
one or another approach? Any pros and contra in the sence of
performance, storage, way of using...?

Thank you very much in advance.

Erika Grondzakova