Multiple Foriegn Keys from One Table linking to single Primary Key in second Table

Posted by croker10 on Stack Overflow See other posts from Stack Overflow or by croker10
Published on 2010-12-30T21:43:39Z Indexed on 2010/12/30 21:54 UTC
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sql

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foreign-keys

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primary-key

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joins

Hi all,

I have a database with three tables, a household table, an adults table and a users table. The Household table contains two foreign keys, iAdult1ID and iAdult2ID. The Users table has a iUserID primary key and the Adult table has a corresponding iUserID foreign key. One of the columns in the Users table is strUsername, an e-mail address.

I am trying to write a query that will allow me to search for an e-mail address for either adult that has a relation to the household. So I have two questions, assuming that all the values are not null, how can I do this?

And two, in reality, iAdult2ID can be null, is it still possible to write a query to do this?

Thanks for your help. Let me know if you need any more information.

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