Difference between primary key and unique key ?
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Answer Posted / sunil upadhyay
the basic difference is that primary key can not have null
value whereas Unique key can have null values.two null
value are not same.One table may have more than one Unique
Key Constraint
columns, but should have only one Primary Key Constraint
column.
| Is This Answer Correct ? | 88 Yes | 51 No |
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