What is difference between UNIQUE constraint and PRIMARY KEY
constraint ?

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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