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What is difference between UNIQUE constraint and PRIMARY KEY
constraint ?
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Answer Posted / naren
When ever you create a primary key constraint on perticular
column in a table it creates clustered index by default,
it cannot allow null values and a table having only one
primary key constraint. But in the case of Unique Key
constraint, it allow only one null value, it creates non-
clustered index by default and a table having multiple
unique key constraints.
Regards
Naren Krishna
| Is This Answer Correct ? | 8 Yes | 3 No |
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