What is the difference between Primary Key and Unique key?
|Primary Key||Unique Key|
|It is used to serve as a unique identifier for each row within a table.||Used to determine rows that are unique and not a primary key in a table.|
|It cannot accept NULL values.||Unique Key can accept NULL values.|
|There is the only scope for one primary key in any table.||Multiple Unique Keys can be defined within a table.|
|The primary key creates a clustered index.||Unique Key creates a non-clustered index.|
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