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Databases

Steve Meadows
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Steve Meadows
Full Stack JavaScript Techdegree Student 15,218 Points
Posted by Steve Meadows
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Steve Meadows
Full Stack JavaScript Techdegree Student 15,218 Points

DataBase Foreign Keys

This is just a question thats on my mind relating to the Database Schema used in this video.. it shows the user_id has a relationship with both tables, the voting table and the books table.

I didn't think you could create 2 foreign keys from one ID? only reason i ask is because i am replicating this schema in a MYSQL database.

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

You forgot to provide a link to the video, but just in general there's no limit.

Each foreign key is enforced independently by the database system. You can have as many foreign keys in a table as you want.

And a table can have only one primary key, but it can be referenced as a foreign key in any number of other tables.