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Foreign Key and Not Null

Posted on 2007-04-03
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Last Modified: 2010-03-20
Hi

Just a basic question.  You can't have a foreign key on an item that is not null.  Is this correct?

Greg
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Question by:greg_c
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Guy Hengel [angelIII / a3] earned 125 total points
ID: 18842173
?
no, that is not correct.

you can have a foreign key pointing from and pointing to a field that is not null.
however, you will need to have the referred value in the "master/lookup" table be present BEFORE you use that value in the child table.
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by:greg_c
ID: 18842235
Thank you
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