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Date: Mon, 18 Aug 2003 23:59:34 -0400
From: "Vernon Smith" <vwu98034@lycos.com>
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I am working on an application system refinement. There is a user profile table in the current system. After the refinement, there are new separated roles, A and B, of the users. The role A only has a few valid fields of the original profile table while the role B still has the whole profile table. In regarding of the DB scheme design, that should be an ideal case of using inheritance. I can have something like

table PROFILE_A ( 
ID int &#8211; PK,
...
):

table PROFILE_B {
...
inherits (A)
);

However, there is a problem. There are some multi-valued field tables, such as languages the person can speak, associated with the profile table referred by ID in the profile table. These tables are still needed for the A and B. But, the ID is not accessible from the PROFILE_B. 

What is the best solution for this DB scheme problem? 

p.s. I can't use array data type for the multi-valued fields since they need to be workable with a selection statement, nor xml or comma separated format for maintainablity concern. 

Thanks,

v.


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