Re: primary key and existing unique fields

Sally Sally wrote:
> Hi all,
> I am wandering about the pros and cons of creating a separate serial
> field for a primary key when I already have a single unique field. This
> existing unique field will have to be a character of fixed length
> (VARCHAR(12)) because although it's a numeric value there will be
> leading zeroes. There are a couple more tables with similar unique
> fields and one of them would need to reference the others. Does anybody
> see any good reason for adding a separate autoincrement primary key
> field for each table? or either way is not a big deal.

Your primary key should not be directly related to the data being
stored. Outside of the fact that it is the primary reference or the row.

Sincerely,

Joshua D. Drake

> Sally
>
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