Unique key allows null values while primary key does not.

• Primary key is a unique identifier for a record in a table.

• Unique key allows null values but primary key does not.

• A table can have only one pri...read more

Unique Key it's accepted null value but don't accept duplicate.

Unique Key get unique value.

Primary key it's a combination of not null and unique Key.

It's doesn't accept null and duplicate value.

Primar...read more