Can a Column be Nullable, Unsigned and a foreign key?

Question

I have several tables which I want to reference to a particular table tools. I have multiple foreign keys assigned to this table. Some times, these foreign keys may not have values but sometimes they do.

I want to know if it is possible for a column be nullable, unsigned and a foreignkey at the same time? Am I sounding sensible or am I completely wrong? Just for the information, I'm using MySQL if it is platform dependent.

score 0 · Accepted Answer · answered Dec 17 '14 at 22:28

0

Shouldn't be a problem to do so. Are you getting any errors when you try?

answered Dec 17 '14 at 22:28

Erik

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I'm dealing with a bunch of live applications. So I want to make sure before proceeding. I didn't try. I can always make it foreignkey and nullable. But if it is unsigned, will it go with nullable. Thats what bothering me. – user1012181 Dec 17 '14 at 22:29
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Make a copy of the database and try it there. That's what staging and testing enviroments are for. – Erik Dec 17 '14 at 22:30
Okay, will try it and let you know. – user1012181 Dec 17 '14 at 22:31
Yes, it is possible. Works fine. – user1012181 Dec 17 '14 at 23:50

Can a Column be Nullable, Unsigned and a foreign key?

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