##

> #
> f Bob has more that one shirt in his
> closet, you might want an entry for each in the Wardrobe table. If you
> key on Person and Clothes, this would generate a key violation.
> #
>
> Accepted - if person/clothes is not unique it can't be a PK.
>
> What's the argument for a generated key if person/clothes is unique?

Because it has business meaning. If your client/boss tells you that the
next
update of WardrobeManager.exe should allow multiple shirts, you will need to
do a lot of changes on your DB to allow it, if you used a generated key that
has no business meaning, the change will be a lot easier
##

Hi Phil,

What if Wardrobe merely states that person HAS clothes - i.e. Bob HAS a
shirt , we're not interested in how many or what colour and we're the
client/boss, so it's NOT going to change?

I simply want to know if Bob has a shirt or Fred has trousers.

Is there still a case for a generated key? How would I use it if I wanted to
find out if Bob has a shirt?

What would be the point?

As I said previously I use generated keys in all base tables (where the pk
may be a fk in another table) but still don't understand why you'd use one
here.

Ray




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