What Is Difference Between Unique And Primary Key Constraints?

1.	What Is Difference Between Unique And Primary Key Constraints?
Answer» An UNIQUE KEY can have NULL WHEREAS PRIMARY key is always not NOT NULL. Both bears unique values. An UNIQUE key can have NULL whereas PRIMARY key is always not NOT NULL. Both bears unique values.

Answer»

An UNIQUE KEY can have NULL WHEREAS PRIMARY key is always not NOT NULL. Both bears unique values.

An UNIQUE key can have NULL whereas PRIMARY key is always not NOT NULL. Both bears unique values.

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