Unique-Duplicates not allowed Nulls allowed Not null-NUlls not all

what are the advantages of primary key over unique+notnull

Question Posted / charumathi

Answer Posted / charumathi

Unique-Duplicates not allowed
Nulls allowed
Not null-NUlls not allowed
Primary key-No Duplicates
No Nulls
A Foriegn key can refer to the primary key.

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4 Yes

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