How to handle Foreign key for optional field in .NET

Posted by brz dot net on Stack Overflow See other posts from Stack Overflow or by brz dot net
Published on 2010-03-23T09:11:50Z Indexed on 2010/04/10 8:33 UTC
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Filed under:

foreign-key

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ASP.NET

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c#

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sql-server

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database

What is the best way to handle following situation?

A dropdown(for master table) is optional in a particular form. But, In database table the field is constrained with foreign key. If user don't select from dropdown then It creates problem because of foreign key.

One solution is to create default option in master table and use it in case of blank selection. but in dropdown, we need to handle this to show on top. Is it perfect solution? Is there any other optimized solution for this?

Thanks

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