If we declare constraints Unique and Not null on a single
column then it will act as a Primary key, so what is the use
of primary key??
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Answer Posted / ashok
Internally , There is same as primary key and unique not null.
You can say unique + not null is higher step of primary key .
So there is no basic difference between this two.
| Is This Answer Correct ? | 7 Yes | 11 No |
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