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Difference between primary key and unique key ?
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Answer Posted / vaithianathan
primary key not accepts null value and
not allows duplicate values.
but Unique key not allows duplicate values
but it accepts ONLY ONE NULL VALUE.
only one primary key allowed per table
we can create multiple unique keys
on the table
By Default, Primary key creates Clustered Index and Unique key Creates Non Clustered Index
| Is This Answer Correct ? | 3 Yes | 0 No |
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