Foreign key on table A --> B, AND foreign key on table B --> A. How is this done?

Posted by unclaimedbaggage on Stack Overflow See other posts from Stack Overflow or by unclaimedbaggage
Published on 2010-05-21T10:29:35Z Indexed on 2010/05/21 10:40 UTC
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db

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schema

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mysql

Hi,

I have two tables - 'business' and 'business_contacts'.

The business_contact table has a many-to-one relationship with the business table. Furthermore, each business has a 'primary contact' field - which I'd assume is a one-to-many relationship with the business_contacts table.

The problem, of course, is that this creates a catch-22 for data insertion. Since neither field can be null, I can't insert a business_contact until I have a corresponding business, but I can't insert a business until I have a corresponding business_contact.

If anyone could help me get my head around how mutual one-to-many relationships are supposed to be dealt with I'd be most appreciative.

(Project being done in MySQL if it makes any difference)

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