Re: Newbie question about db normalization theory: redundant keys OK?

-CELKO- <jcelko212_at_earthlink.net> wrote:

>>> If teachers are permitted to change their names, then names are not appropriate keys for teachers. <<
>
>Agreed; this was a skeleton table to demonstrate to the OP that tables
>can have redundant or even overlapping keys to preserve data
>integrity. Tony just gets easily side tracked and I am afraid I tend
>to fall for it myself. Sorry for the thread drift ..
>
>Instead of a teacher's name, we can tattoo a permanent bar code on the
>foreheads of the faculty, using their tax identification number :)

     That does not allow for internationali[sz]ation.

Sincerely,

Gene Wirchenko

Computerese Irregular Verb Conjugation:

     I have preferences.
     You have biases.
     He/She has prejudices.