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Categories >> Software >> Databases >> MySQL
 


 

 
Question What is the difference between primary and unique key
 Question Asked In Companies :: CSC,     < I also faced this Question! >
 Question Submitted By :: kamaltimalsina012
  Answer Posted By  
 
Answer
Primay key restrict the duplicacy in the records and does
not accept null value or there are only one primary key in
a table

Unique constraint also restict the duplicacy but it accept
the null value one or more then one. We can apply unique
constraint more than one column

Is This Answer Correct ?    2 Yes 2 No


 
  ashish asthana
 
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