Subject | Re: [ib-support] Re: time series and FB/IB |
---|---|
Author | Ray Drew |
Post date | 2002-12-10T15:03:38Z |
Louis wrote:
#
I use a generated key in a many-to-many situation when there is a
possibility of duplication. If 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?
Ray
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#
I use a generated key in a many-to-many situation when there is a
possibility of duplication. If 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?
Ray
__________________________________________________
Do You Yahoo!?
Sign up for SBC Yahoo! Dial - First Month Free
http://sbc.yahoo.com