what is the difference between primary key and unique key?

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what is the difference between primary key and unique key?..

Answer / karishma39malik@gmail.com

primary key means... a key that is unique among all keys.. n
has no duplicate values and no repeated columns...
unique key is a key defined uniquely among all keys...

Is This Answer Correct ?    2 Yes 0 No

what is the difference between primary key and unique key?..

Answer / swi

1.IN ABAP Primary key is having null values where as in
unique key having no null values

Is This Answer Correct ?    5 Yes 4 No

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