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Difference between primary key and unique key ?
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Answer Posted / sandhya
Primary Key cannot contain null values
Each table has one and only one Primary Key
Primary Key is used to reference as Foreign key while
performing table joins
Clustered index is created on Primary Key
Unique Key can contain null value
A table can have any numberof unique keys
Non-clustered index is created on unique key columns
| Is This Answer Correct ? | 2 Yes | 1 No |
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