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What is differance unique key and primary key.

Answer Posted / madhu

unique key:
1.unique key will accept more than one null value.
2.whenever u created a unique key, then internally one non-clustered index will be created(one table can have more than one Non-clustered index).
3.one table can have more than one unique key.
Primary key:
1.One table should have one primary key only.
2.primary key will not accept null values.
3.whenever u created a primary key then internally one clustered index will be created(one table can have only one clustered index).

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