PRIMARY KEY or FOREIGN KEY?

takeda14121990 · June 11, 2017, 7:24am

Say I have a users table with uid, name, email, and password with a PRIMARY KEY on uid and a UNIQUE KEY on email.

Now I want to create a profiles table with uid, and other extended profile information. Should uid be a PRIMARY KEY or a FOREIGN KEY referencing uid from users in this case?

mirfan · June 20, 2017, 4:52pm

Profile table UID column should be foreign key referencing UID from users table.

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PRIMARY KEY or FOREIGN KEY?

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