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Difference between primary key and unique key ?
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Answer Posted / rinu
1)unique key can be null but primariy key cant be null.
2)primariy key can be refrenced to other table as FK.
3)we can have multiple unique key in a table but PK is one
and only one.
4)PK in itself is unique key.
5)a table can have more then one unique key column but a
table can have only one primary key column.
6)primary key creates clustered index but unique key
creates non clustered index.
| Is This Answer Correct ? | 12 Yes | 7 No |
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