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Primary and Composite keys

kiss07
99
Dear Friends,

One table How many primary keys are allowed?
same as
How many unique keys are allowed?
What is composite keys?

Thanks,
Kiss07.
Jan 5 '07 #1
2 2172
Okay . This one is straight. A Primary key is that ----- Primary i.e. ONLY one. I think what you want is to know if mulitple columns can combine to form one Primary key . The answer is yes, and that is a composite key. A unique key is unique but maybe a foreign key as well. A foreign key is a key that refers to a primary key in some other table. Hope this is useful to you
Jan 10 '07 #2
MMcCarthy
14,534 Expert Mod 8TB
Please give proper titles to your questions rather than Need Help ...

ADMIN
Jan 12 '07 #3

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