Difference between primary key and unique key ?

Answer Posted / ankit kumar singh

Primary Key:
* Primary Key can not contain null value
* Clustured index is created in Primary key.
* Primary Key allows Each row in a table to uniquely
identified and insures that no applicable row exists.

Unique Key:

* Unique Key can contain null value.
* More than one Unique key in a table can be declared.
* Non-clustered index is created in unique key.

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