what is difference between foreign key and reference key

Answer Posted / anup

very simple...we use primary key or foreign key whenever we need to make relation.ex..if we need to join student (Roll P.K) and marks(roll F.K.) then we can join both tables only if we have primary key in one table and foreign key in other..one table may have n numbers of foreign key and n number of primary key (Called composite key)..mail me if u need more details in oracle or any front end lang...anup from chennai,Ranchi.

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