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The Basics of Creating Tables in SQL

Primary keys – the basics
Single-column primary keys
11. There can only be one...
Multi-column primary keys
NOT NULL
Review

Instruction

Great! Another important thing you should know about primary keys is that there can only be one primary key in a table. Let's delve into that.

Exercise

Run the template query we created for you. As you might notice, we tried to set both the id and title columns as the primary keys. Do you think we will succeed?