Difference between Primary key and unique key?

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Difference between Primary key and unique key?..

Answer / deepali b. baviskar

Unique key can be NULL but Primary key couldn't be NULL.

Is This Answer Correct ?    11 Yes 0 No

Difference between Primary key and unique key?..

Answer / sraboni mondal

primary key is a key which is totally unique key and unique
has null values

Is This Answer Correct ?    0 Yes 1 No

Difference between Primary key and unique key?..

Answer / sohini ghosh

In RDBMS, a unique key can uniquely identify each row in a
table, and is closely related to the Super key concept. A
unique key comprises a single column or a set of columns.it
can be null.


A primary key is a special case of unique key. Primary keys
may consist of a single attribute or multiple attributes in
combination.It can't be null..

Is This Answer Correct ?    0 Yes 2 No

Difference between Primary key and unique key?..

Answer / keerthi

primary key is a field that can serve as unique identifier in table.ex:customer id.

Is This Answer Correct ?    1 Yes 4 No

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