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    anandpocham's Avatar
    anandpocham Posts: 1, Reputation: 1
    New Member
    		  
    #1

    Nov 20, 2006, 10:21 PM
    E-R Diagrams
    Hi,

    My Question 1 is, When we are trying to give a relation with Foreign key referencing only a part of the composite key, it is not accepting the relation. Is it possible?

    2. The Foreign key referencing the primary key of multiple tables referencing only one table at a time, is it possible?
    ScottGem's Avatar
    ScottGem Posts: 64,966, Reputation: 6056
    Computer Expert and Renaissance Man
    		  
    #2

    Nov 21, 2006, 07:31 AM
    First I am not a fan of composite keys. It just makes building relations that much harder. A PK should be a unique identifier used internally by the database. While I don't go so far as some to state the PK should be hidden from the user, it should have no relation to real data. By using such a PK you remove the problem of relations with composite keys.

    I don't understand the second question.
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